Police secure the scene where a mail carrier was shot to death Friday evening in Milwaukee.
CNN  — 

A mail carrier was shot to death Friday evening in Milwaukee, police said.

Police said the 44-year-old man had worked for the US Postal Service for 18 years. They did not release his name.

“The Milwaukee Police Department sends our sincere condolences to the victim’s family and to the USPS for the loss of their member,” the department said in a statement.

Investigators did not provide any information about suspects or motive.

The US Postal Inspection Service is leading the investigation.

“The safety and security of Postal employees is a top priority,” the agency said in a statement.

“The shooting death of a Milwaukee postal worker is alarming. My thoughts are with the victim’s family and colleagues. The postal worker in this homicide was a public servant, which makes this crime even more disturbing,” Mayor Cavalier Johnson said in a statement.

A reward of up to $50,000 is being offered for information leading to the arrest and conviction in the homicide, according to Chicago Division of the U.S. Postal Inspection Service.

“The suspect vehicle is described as a silver Audi Q5 SUV with tinted windows,” the USPIS said in a tweet. “The suspect(s) should be considered armed and dangerous.”

Anyone with information is asked to call the USPIS at 877-876-2455 with any tips and reference the case number 3927094, the agency said.

CNN’s Raja Razek contributed to this report.