Dropbox played an instrumental role in arresting a corporal in the US Army Reserve on charges of child porn possession, according to an arrest affidavit from the Austin Police Department seen by Business Insider.

The affidavit said a 27-year old man named Michael Nieto is in custody at the Travis County Jail after a tip from Dropbox indicated he had 38 child porn videos uploaded to the cloud storage service.

Dropbox filed a report last month through the National Center for Missing and Exploited Children's CyberTipline, which led to the local police tracking the account and discovering pornography that involved a girl appearing to be under the age of 8, the affidavit said.

Nieto later admitted to the charges and told the police that he had traded more files with other people, according to the affidavit. His bail is set at $100,000.

Dropbox states in its user agreement policy that users must not attempt to "publish or share materials that are unlawfully pornographic or indecent, or that contain extreme acts of violence." The company would not comment on the specifics of this case, but sent Business Insider the following statement in response to the report:

Child exploitation is a horrific crime. Whenever law enforcement agencies, child safety organizations or private individuals alert us of suspected child exploitation imagery, we act quickly to report it to the National Center for Missing & Exploited Children (NCMEC). NCMEC reviews and refers our reports to the appropriate authorities. We’re deeply supportive of their important work in the fight against the exploitation of children.

Dropbox isn't the only software company helping fight child sex trafficking issues. Microsoft once donated its PhotoDNA software, which helps identify online photos and videos, to law enforcement agencies to help rescue victims of child sex abuse.

In 2013, Twilio, a communications software maker, partnered with Salesforce and the Polaris Project to launch a free text messaging campaign, so child sex trafficking victims could ask for help. Even a Y-Combinator startup called Rescue Forensics has built software for law enforcements to collect online evidence that could be used to prosecute human traffickers.