Texas police said they were seeking Alberto Morales, 42, a violent sex offender who stabbed a Miami-Dade County, Fla., police officer and escaped in the Dallas area while being transported to Nevada.
Morales, was described as "armed and dangerous," by The Dallas Morning News reported.
The Texas Department of Public Safety activated its seldom-used Blue Alert, and police in Grapevine, Texas, said Morales may have stolen a vehicle, a white 2008 Ford sport utility vehicle, from an Irving, Texas, motel, the newspaper said.
Morales was in the custody of two Florida officers transporting him from Miami to Las Vegas for a court hearing when they said he began acting "strangely." During a layover in Dallas, they decided to rent an SUV and drive the rest of the way.
Shortly after leaving the airport, one of the officers stopped at a Walmart, leaving the other officer in the vehicle with Morales, police said. While the one officer was inside the store, Morales stabbed the remaining officer several times and escaped, Grapevine police spokesman Lt. Barry Bowling said.
Police said Morales was still shackled to a belly belt when he escaped.
Morales was described as 5-foot-7, 175 pounds, with brown eyes and hair and of Cuban descent.
The injured officer underwent surgery and was expected to recover.