Totally fine

Don't let anybody in

Toshinori glared at young Aoyama, who glared back. "Kid?" He played dumb, as if he wasn't aware of the warning signs. Aoyama stood next to him, his gaze piercing Toshinori's flesh.
"It didn't took much time" said young Aoyama, his hand reached to his pocket. "What do you mean?" Toshinori continued with his act. "I didn't buy enough time!" Aoyama shouted the last word as he jumped on his teacher, a knife in his hand that was previousley tucked in his pocket. Toshinori sacrificed his left palm, stoping the knife's trajectory with it, the blade now stuck in his flesh.
Thick blood streamed down his arm into his sleeve when he pushed the kid off of him and near the broken window. "What is your motive, young Aoyama?!" Toshinori thundered. "None of your bussiness, All Might!" Aoyama replied.

At last, Toshinori managed to shove the kid back, away from him and young Midoria, but when he tried to catch Aoyama to capture him, the kid stumbled back to the balcony. Aoyama slipped on a shard of glass, dislodging a part of the safety railing.
Toshinori wasn't fast enough. Aoyama fell down from the balcony, a soft cry escaping his lips before a 'sploch' sound was heard. When the tall blonde looked over the broken railing, all he saw was a puddle of dark goo. He knew immediately what this goo was, and who this quirk belonged to.
'That means that the real young Aoyama might have been captured by the League' he frantically realized, going back inside to treat his bleeding palm and guard his successor.

A commotion was heard from the other side of the door. The kids woke up, most probably. "What was that noise?" He heard Tokoyami's voice asking in a calmly manner.
Toshinori opened the door and stepped outside Midoriya's room, his glance hovering over the kids in the corridor. He didn't see more than a few kids. "Young heroes" Toshinori reised his voice, he wanted them to notice him.
Six surprised faces turned to look at him, Aoyama's was not one of them. "Young heroes, you are required to return immediately to your rooms and wait for orders and explanation from me. Everyone in their own rooms, curfew time had long since passed" he observed their faces as he spoke, searching for odd behaviour.
"All Might sensei, what had happened?" Kaminari asked, getting a supporting nod from young Tokoyami. "I will explain through text message, now go!" All the teens dispersed to their allocated rooms. All except one.

"Young Bakugo, have you heard what I sa-" the angry teen approached Toshinori, shouting "yeah I heard you, but I need to check the shitty nerd first, to see if he's alright". Bakugo almost got passed the teacher when a large, bandaged palm blocked him.
"You will do as I said, young Bakugo, it's not negotiable". "What the-" Toshinori shoved him back, "to your room". Young Bakugo opened his mouth to response, but he must have seen the determination and the glint of determent in his teachers eyes, so he stumbled back before turning his back toward the tall man.
"You better keep him alive for me, All Might" the kid muttered. "That's what I'm aiming for" he replied quietly.
Toshinori closed the door, grabbed his phone and started typing as fast as he could. He reviewed his message before sending it to every kid in class 1-A, and then rephrased it with some extra details and sent it to all faculty members of UA.

'Young heroes, you are required to stay in your rooms and lock the doors. A trespasser was seen near our dorm building and is currently being chased by your teacher.
You are not to open the door to no one, and be alone in your own room. Don't let anybody in, even if they identify themselves as your teachers or classmates. We don't know yet how many enemies had infiltrated campus, nor we know their motive.
Anyone that discover a suspicious movement or person is to let me know immediately. Stay safe and do not engage in any fight unless absolutely necessary.'

Toshinori sat there, running the encounter with Himiko Toga again in his mind. The teen villain took the appearance of young Uraraka, which required the young heroine's blood (according to the intel they had on Toga's quirk). That meant that young Uraraka might be in grave danger.
So now Toshinori had two students that are most probably in a dangerous situation at the moment- Uraraka and Aoyama.
'I need to contact Nezu about it, it is our top priority to protect the students. And I will need to do a head count in some way or another, and ask the other teachers to perform head counts for all classes in campus. We must know if anyone is missing besides young Aoyama and Uraraka'.
He went over the text he sent, checking who opened it. Young Uraraka's phone was listed as such. Toshinori called the girl's phone number.

"Hello, All Might sensei? What is happening? Is Deku kun and the others okay?" Uraraka's sleepy voice was heard through the device.
"Are you in your room, young Uraraka?" Toshinori asked cautiously. "Yeah, you asked us to wait in our rooms" she replied, "but you didn't answer my question, sensei". "I'm sorry, you are right. Young Midoriya is okay, as for your classmates I believe they are all okay as well. Please report to me if anything happens, okay?". "Sure, sensei" said the girl and they hung up.
Toshinori called Nezu after verifying young Aoyama did not open his text message. "Yagi, I read your message. I will need you to elaborate more regarding the missing students and the incident itself" said the rodent.

Toshinori spoke to the principal, explaining the entire chain of events. Aoyama's location and well being still unknown, Uraraka's presumed sound state, Aizawa's current occupation. The rat listened carefully before making the decision to let Aizawa continue the chase after Toga by his lonesome.
"You did good, Yagi san. Now stay with Midoriya and keep an eye on the others. I will update you with more details as we go".
Toshinori sat next to his successor's bed, noticing the shiver of the kid. With the window broken, nothing prevented the chill of the night air from infiltrating inside the room, agonising young Midoriya's fevered body. The boy sneezed and coughed relentlessly, and it seemed as if his penetration wound from Toga's device kept bleeding through the bandages Aoyama's double put on him.

"Young Midoriya, are you awake?" The man tried speaking to him, his hand on the sick kid's forehead. This was not good, the boy was in a really bad state and needed medical attention and a new room.
"All... Mi... c-cold" young Midoriya whispered, his eyes half lidded as he looked at Toshinori. "I know, you're cold, I will look for another blanket, but there is nothing else I can do at the moment. It is too risky to leave this room with you like that" the blonde had to watch Midoriya cough these horrible, horrible coughs and could not help.
He draped another warm blanket around the kid's shivering body. He needed to at least find a way to stop the bleeding, but besides puting pressure on the wound he didn't know how.

"This is going to hurt, I'm sorry in advance" said the man. He took young Midoriya's wounded forearm out of the blanket and in his injured hand, one tear forming in his eye, for he knew that what he's about to do will be tough for the both of them.
Toshinori inhaled, and then pressed his healthy palm as hard as he could on Midoriya's bandage.
The kid gasped sharply before screaming. By the feel of it, his forearm was more injured than it seemed, the bone cracked under Toshinori's hold. Midoriya was crying, pleading for mercy from his unidentified torturer, by the gist of the words the blonde could hear him mumble.
"I'm sorry kid, I'm so so sorry" he whispered, pressing harder. Soon enough, the boy passed out and Yagi was left there, holding the kid's limp arm and praying that Aizawa will capture the villains as quickly as possible.

Aizawa chased Toga into one of the training facilities in campus. It was the notorious Ground Beta, the urban battle field. Toga most probably had a huge advantage in a cityscape, considering that is the environment she usually hide in. But, well, Aizawa was no stranger to the urban zone as well.
Aizawa knew the ins and outs of Ground Beta, and he could use it to his favor.
Shouta held his capture weapon tightly, looking around him and had his ears to any noise the girl might invoke. Footsteps, to his right. Her bare feet made the most delicate of sounds, but to an underground hero as Earaser Head it could not go unnoticed.
Few moments later, Toga was already captured by him, squirming.
"Who else is here, Himiko Toga?" Shouta growled, an angry tone to his speech.

A longer episode, as an apology for my disappearance. Thank for the patience, and for the support!