"With the advance of the technology and the phones and the encryption, law enforcement at the state, local, and federal level is increasingly not able to get into these phones," said FBI special agent Christopher Combs.

FBI official, citing encryption tech, says federal agents have not been able to access the Texas shooter's phone https://t.co/CacbcOGFxq — NBC News (@NBCNews) November 7, 2017

Combs didn't indicate which phone the Texas shooter had used, for fear that it would promote security capabilities of that device in particular. The agency transported the smartphone back to its offices in Quantico, Virginia for analysis. He also didn't mention whether the FBI had requested help from whichever company had created the smartphone in question, as it had back in 2015 when it couldn't access the San Bernardino shooter's iPhone.

Nor would the agency necessarily need to. After Apple refused to create a backdoor that would surpass its own phone's security, a tool that likely would have been used in investigations in the future, the FBI reportedly paid a vendor $900,000 to break into it. And despite repeated attempts, last month a judge cited national security concerns when she blocked multiple journalistic outlets' FOIA requests for information about the tool and whomever built it.