A Metro Transit police officer was injured in a small explosion before a training exercise in St. Paul on Wednesday afternoon.

Paramedics took the officer to Regions Hospital with non-life threatening injuries, said Howie Padilla, Metro Transit spokesman.

The K-9 officer was preparing for a police dog bomb detection training exercise about 3:30 p.m. at 515 N. Cleveland Ave., which is the Metro Transit Overhaul Base, where bus maintenance and repairs occur.

“He was putting out a device with a small amount of explosives and, for whatever reason, the explosives ignited,” said Padilla, who added an investigation is underway into what happened.

The St. Paul police bomb squad was called out and neighboring buildings were evacuated as a precaution.

Officials did not immediately describe the injuries of the officer, who has been with Metro Transit for seven years. His K-9 partner was still in the vehicle at the time of the incident.