One person was killed in a blast, purportedly caused by an “explosive device,” in a car in a Berlin suburb early Tuesday. The explosion reportedly occurred as the car was moving through the western district of Charlottenburg, heading toward the city center.

Following the explosion, which killed the driver and flipped the vehicle up in the air, local police tweeted video footage from the site, showing officers warning local residents to stay indoors and to keep away from windows.

“We can't say anything about the cause. We are at the beginning of our investigation,” Michael Merkle, a Berlin police official, reportedly said. “Forensic investigators are here, will carefully examine the car, everything will be examined. The homicide division is on site and will take over the further investigation.”

Meanwhile, the deputy chief spokesman for Berlin police, Carsten Mueller, told the Associated Press (AP) that “investigators are working on the assumption that it was an explosive device,” inside or on the vehicle, that caused the blast.

Mueller also told the AP that investigators were still trying to determine the victim’s identity. Experts checked the vehicle but found no further explosive devices.

The motive for the apparent attack and the circumstances surrounding the explosion are not immediately clear. However, according to German newspaper Der Spiegel, investigators have already ruled out terrorism.