HUMBLE, Texas – A Dayton Independent School District music teacher is accused of possessing hundreds of images of child pornography.

Investigators said Joshua Lee Janecka, 31, had several hundred images and video of underage boys performing sexual acts on a laptop at his Humble home.

According to court documents, officers received a cyber tip from Microsoft about one of its users.

VIDEO: Dayton ISD teacher accused of child porn appears in court

Investigators with Harris County Constable Mark Herman's Office of Criminal Investigations Division said they received information from the National Center for Missing and Exploited Children about a person in the Humble area believed to have possession of child pornography.

“We immediately started the investigation and through search warrants and subpoenas started to monitor his electronic activity at home and it certainly showed that he was downloading pornography,” Herman said.

He said the Precinct 4 High Tech Crimes Unit took about four days to conduct their investigation after they received the tip.

After executing a search warrant April 4, investigators found three images of child pornography and a chat log, according to documents. Officers tracked the IP address to Janecka’s home, where on they found "an abundance of images, literature and videos of children being sexually exploited and sexually assaulted," investigators said.

“Oh man, that’s just, I can’t even think that could be right behind you, that’s insane,” said Jordan Walker, who lives on the same floor as Janecka.

He said when he woke up for work around 5 a.m. Wednesday, he heard a lot of commotion and when he went outside, he saw dozens of officers.

“I never saw the guy until they brought him down in handcuffs,” Walker said. “It’s almost unbelievable, you really can’t believe someone would do something like that, but as a father, I think my natural instincts kick in and it makes me want to protect not just my daughter but other kids as well.”

WATCH: Constable Mark Herman speaks on teacher accused of child porn

Investigators also went to Dr. E.R. Richteer Elementary, where Janecka is employed as a music teacher, and seized his computer for analysis.

“My main concern is shoring up our case and getting the word out to the parents in that area in case their kids have had any exposure with this guy,” Herman said.

Investigators said Janecka admitted to making and using his Microsoft account for child porn.

Janecka is also believed to have been associated with the Boy Scouts of America as a Scout leader and a swim instructor for children for several years, according to investigators.

The 31-year-old, who served in the Marine Corps between 2005 and 2009, made his first court appearance Wednesday and is charged with five counts of possession of child pornography and one count of promotion of child pornography.

His bond was set at $2,500 for each charge of possession and $10,000 for the charge of promotion, making his total bond amount $22,500.

Richter Elementary parents said they were stunned by the allegations.

"Finding out something like that is really scary. You send your child to school hoping and praying they'll be safe,” said Rechal Papillion, whose daughter attends the elementary school.

Dayton ISD released the following statement:

"Dayton ISD was notified of an arrest in Harris County of a Richter Elementary teacher. We are fully cooperating with their investigation. We have placed the teacher on administrative leave while their investigation continues.

"In an effort to keep parents informed, letters will be distributed to all Richter Elementary students this afternoon.

"Mr. Janecka is a first year educator, serving as a music teacher for Dayton ISD. Mr. Janecka has been placed on administrative leave pending the outcome of the investigation."

Janecka is expected back in court Friday.