The City of Dallas reported that T-Mobile phones were spontaneously dialing 911, a problem that has been reoccurring since November, tying up the call center for up to hours at a time. At one point on Saturday, the city reported that 422 calls were on hold.
T-Mobile may be off the hook for the deaths of two Dallas residents who had trouble reaching 911 operators earlier this month.

City officials said Thursday that so-called "ghost calls" from T-Mobile customers are not to blame for a flood of calls to 911 operators in Dallas that clogged the system and led to longer than usual wait times. Ghost calls happen when a phone repeatedly dials 911 without the caller ever knowing it's happening. Each call registers as a hang up and requires operators to call back, clogging up the system and making it hard for legitimate emergency calls to get through.

Dallas City manager T.C. Broadnax said at a press conference Wednesday a ghost calling issue with T-Mobile customers had been identified in October and that after several months, it looked as though it had been resolved in January. But a spike in calls occurred again in March, leading officials to believe that the problem hadn't been corrected.

The problem took on a new sense of urgency this week following the death of six-month old Brandon Alex, who died on Saturday after his babysitter was unable to connect with a 911 operator. The glitch had also been blamed for the death of 52-year old Brian Cross, who died at a local hospital in early March after emergency responders were delayed getting to him because his husband had been on hold for more than 20 minutes waiting to speak to a 911 operator.

Initially, Dallas City manager T.C. Broadnax and Dallas Mayor Mike Rawlings pointed fingers at T-Mobile. In a statement Tuesday Rawlings said it "was outrageous T-Mobile still has not resolved the ghost call issue that is putting Dallasites in danger by clogging our 911 system."

T-Mobile executives, chief technology officer Neville Ray and executive vice president David Casey, along with several engineers arrived in Dallas early Wednesday to help Dallas officials figure out what has been causing the latest problems.

T-Mobile's assessment is that these most recent incidents cannot be blamed on ghost calls, according to the city. Instead, the problem appears to be caused by people hanging up before they reach a 911 operator and then redialing. To address this issue, Dallas officials said it will add a dozen additional call takers starting this weekend to make sure all calls are answered.

T-Mobile hasn't commented separately on the situation since Wednesday at the press conference when Ray said the issue appeared to be unique to the Dallas call centers. He said T-Mobile hasn't seen anything similar in the more than 4,000 911 call centers around the country where the carrier's service is offered. This may indicate that the problem could be associated with the technology used by the Dallas call center.

The city also said in its statement that it's "pursuing technology upgrades." T-Mobile has also made some adjustments to its network to ensure a smooth delivery of 911 calls to the call centers, the city added. T-Mobile engineers as well as representatives from other 911-technology vendors will remain in Dallas for the next two weeks to monitor the call centers.

Mayor Rawlings said he was "pleased that our staff and T-Mobile worked through the night and have determined some immediate technological upgrades that will better serve our citizens calling 911."

The incidents come days after AT&T customers in Dallas, as well as in other parts of Texas and Indiana and other states in the Midwest, experienced an outage of 911 service. It's not clear what's behind the issues experienced by AT&T customers. The Federal Communications Commission is investigating the AT&T outage. A spokesman for the agency said Thursday the Dallas Police Department had previously asked the FCC to look into technical issues with 911 in Dallas and that the review is ongoing.