PINECREST, Fla. -- Police pulled over a driver because his taillight was out and discovered the driver's dead girlfriend slumped in the passenger's seat.

Hector Trellez, 30, later told investigators that he strangled Martha Uribe during an argument about their relationship. He drove the body back to their apartment, left it in the car and later began driving around with it, police said.

He was stopped early Saturday by police in Pinecrest, an upscale Miami suburb. Police first though Uribe, 33, was sleeping, than took a closer look and realized that she was dead. Trellez told officers that he strangled her after picking her up after work Friday evening.

Trellez has been charged with first-degree murder.

Uribe wanted to break off the relationship, Miami-Dade police spokesman Detective Juan Del Castillo said.

"Apparently, she wasn't happy for some time, and she wanted it to end," Del Castillo said. "He didn't want it to."

Trellez and Uribe emigrated from Colombia about eight years ago. Pinecrest police turned the investigation over to Miami-Dade County police.