(CBS News) A manhunt is under way in Texas, after a convicted sex offender made a violent escape.
Alberto Morales was being transferred across the country from Miami to Nevada, when he stabbed a detective guarding him Monday night in Grapevine, Texas.
Morales has now been added to Texas' "10 Most Wanted" list, and authorities have offered up a $10,000 reward for information leading to his capture. Some schools in the Dallas suburb are on soft lockdown, and police are asking everyone to be alert in case friends or co-workers unexpectedly fail to show up.
A surveillance video shows Morales escaping his Miami-Dade Police escorts Monday night from a Wal-Mart parking lot near Dallas. While chained at the hands and waist, he somehow managed to break off a piece of his eyeglasses and stab Det. Jaime Pardinas multiple times. Pardinas called 911. He can be heard in the 911 call saying, "I've been stabbed in the neck. Subject is 5' 7", 165 pounds, white Latin male named Alberto Morales. He's a schizophrenic."
Morales was being transported to a prison in Nevada by Pardinas and his partner, Det. David Carrero, who was inside the Wal-Mart at the time.
Carrero can be heard on the call saying, "It's getting hard to breathe for my partner."
According to police, Pardinas is currently in stable, but serious condition.
The three men were originally flying to Carson City, Nev. But they were kicked off the flight during a layover in Houston, because Morales had been disruptive. J.D. Patterson, Miami-Dade Police director, said, "Mr. Morales was very agitated and acting very, very erratic."
The two detectives decided to make the rest of the 1,900-mile journey on land, and were near Dallas waiting for a third detective to join them, when Morales got away.
Sgt. Robert Eberling, of Grapevine Police, said, "This is a dangerous individual, and he's definitely demonstrated how dangerous he is by his criminal past."
In 2003, Morales attacked two women in their Miami apartment, leaving his wallet behind at the scene. Morales pleaded guilty to those crimes in December, and then was ordered back to Nevada, where he had already been convicted of two aggravated sexual assault charges.
Eberling said, "We have a lot of police officers, federal agents, undercover units out there. We're utilizing whatever we can to get this guy apprehended."
Authorities say they believe Morales is still hiding out in the Grapevine area. But they're not taking any chances. They're concerned about him possibly fleeing to Mexico, so they've alerted all border crossings to be on the lookout.
For Dallas-Fort Worth's CBS-11 correspondent Sharrie Williams' full report, watch the video in the player above.
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