There have been a number of iPhone thefts in the U.S. in recent months, perpetrated by “porch pirates” often seen on doorbell camera footage snatching boxes immediately after delivery. According to an article published yesterday in the Wall Street Journal, AT&T phones are being targeted more than Verizon and T-Mobile phones.

“The key to these quick crimes, investigators say, is that the thieves are armed with tracking numbers. Another factor that makes AT&T packages particularly vulnerable is that AT&T does not typically require a signature upon delivery…Verizon and T-Mobile require a signature.” “AT&T generally does not do this when delivering smartphones,” the article says.

The WSJ spoke with Chris Brown, a police lieutenant in Deer Park, Texas, who “said the suspects were armed with inside information: AT&T package tracking numbers. “Deer Park police are working with AT&T to investigate how the suspects obtained this information,” he said.

When contacted by Ars today, an AT&T spokesperson said the phone provider uses multiple delivery companies and “ships tens of thousands of packages per day without incident.” AT&T said that “signatures are required in several markets where there have been theft issues” and that “we regularly make changes to our processes, be it the method of delivery or even the type of packaging, to reduce instances of theft . “these thefts.”

AT&T also said that it “works with law enforcement and package carriers to protect our deliveries” and that these crimes are “committed by sophisticated criminals who are being investigated by both federal and state law enforcement agencies.” We asked both AT&T and FedEx how many thefts there were, but didn’t hear back.

Here’s a WMUR-TV report on such thefts in New Hampshire, complete with doorbell camera footage:

AT&T: No evidence of a hacker attack

The WSJ quoted AT&T as saying it had “no evidence of a breach of our systems and this was not a hack.” If there was no hack, it is possible that the tracking numbers were obtained directly from an employee or contractor. AT&T told Ars that there is still no evidence of a breach or hack.