A United States Postal Service employee fatally shot while driving along Interstate 30 near Sylvan Avenue in Dallas early Monday has been identified.

Police say the driver was 58-year-old Tony Mosby.

Officers were called at about 2:20 a.m. to a shooting at 110 Interstate 30 after the driver of a box truck came to a stop in the eastbound lanes of the Margaret McDermott Bridge.

When officers arrived they found truck driver had been fatally shot and that he was a USPS employee.

Police have not yet determined a motive for the shooting.

Officials have not said which mail center the employee worked out of, but the site of the shooting is less than a half a mile from the Dallas Main Post Office and about two-and-a-half miles from the USPS' Dallas Network Distribution Center.

News of Mosby's shooting death came as a shock to fellow Postal Service employees.

"When we walk through those doors it's never going to be the same, never," said co-worker Denleen Wesley.

Co-worker Felicia Wright has known Mosby for more than 10 years.

"He's a quiet, nice person, easy to talk to," Wright said.

"He wasn't doing anything wrong, and someone kills him. I can't understand it," Wesley said.

Dallas police confirmed Monday the shooting location is about a mile from where someone fired on a police car at about 2:10 a.m. Feb. 8, however police said there is no evidence linking the two crimes.

During the initial stages of the investigation, Dallas police closed the eastbound lanes of the interstate twice and the westbound lanes once. All lanes have since been reopened to traffic.

Monday's shooting is being investigated by the Dallas police and the United States Postal Inspectors. Dallas police and U.S. Postal Service Inspection Service are asking for anyone with information to contact Detective Walton at 214-671-3632 or 214-701-8453.

U.S. Postal Inspectors are offering a reward up to $50,000 for information leading to an arrest and conviction in this case.