ESCONDIDO, Calif. -- A senior U.S. Border Patrol agent was arrested Thursday on suspicion of attacking two people with a hatchet in an Escondido home, leaving a man in critical condition and a woman less severely wounded. New details emerged Friday about the man's troubled relationship with his estranged wife.

Gamalier Reyes Rivera, 32, allegedly assaulted the couple about 1:15 a.m. in a bedroom of his estranged wife's home in the 800 block of South Upas Street, according to police.

Authorities suspect that the attack might have been an unfortunate case of mistaken identity, 10News reported Thursday. Rivera, authorities asserted, could have entered the home with the intent of attacking his estranged wife and attacked the wrong couple instead.

Officers responding to an emergency call found the victims in the residence with severe lacerations, Lt. Bob Benton said. The assailant had fled, leaving behind a hatchet.

Medics took the victims to Palomar Medical Center, where the man was admitted in critical condition with wounds to his neck and torso. His 21-year-old girlfriend was treated for injuries to her legs and released later in the morning.

Shortly after the attack, officers spotted Rivera standing near a telephone booth at Ninth Avenue and Pine Street, a few blocks from the crime scene, Benton said.

Rivera surrendered peaceably and was taken to the same hospital as the victims for treatment of undisclosed injuries. He was booked into the Vista Jail in the early afternoon on suspicion of two counts of attempted murder and was being held without bail.

Border Patrol representatives confirmed that Rivera, an Imperial Beach resident, works for the federal agency. 10News reporter Rachel Bianco obtained court documents that show Rivera is a senior Border Patrol agent.

Several other people were in the home with the victims when the violence erupted but were uninjured, according to police. The suspect's spouse was asleep in another room at the time of the attack, 10News reported.

The motive for the attack was unknown, and it was unclear how the assailant got into the house, according to Benton. There were no signs of forced entry, the lieutenant said.

Bianco reported that the Rivera met his wife, Erika Von Der Heyde Teran, in Venezuela where he was serving as a Marine and she was working at the U.S. embassy. They married in 2002.

The couple moved to Puerto Rico -- where their daughter was born -- before relocating to San Diego in 2003, for Rivera's job with the Border Patrol.

In 2005, Teran filed for a restaining order against Rivera. It read, in part:

"I went in his room to get some papers out and I saw a list. I started reading the list only to discover it was a respondent's plans to kill me. It listed steps about what he needed to buy, gloves, plastic, trash bag, weights. That he needed to find a dark place with no cars, and then described how he would put my body in the bag, weigh it down and destroy the evidence. It even said how he would act once I was missing, really mad. I called the police and they took the letter. The report #05-024925. I am very frightened and the only time I have ever seen him make a list, he has followed through on everything on the list. I need an order of protection for my daughter and I, and to make sure his weapons are taken away."

Bianco reported that the couple got back together in 2007.

On Monday -- three days before the attack -- Teran filed a request for child support and spousal support, Bianco said.