A blast near the office of India’s main opposition political party in the southern city of Bangalore injured 16 people, authorities have said.

Police said the blast could have originated from an improvised explosive device on a motorcycle parked near the office of the Bharatiya Janata Party in the Malleshwaram area of Bangalore, reports the BBC.

The explosion shook nearby buildings and caused several vehicles to burst into flames, leaving dozens wounded, including eight policemen. The injuries are mostly minor, according to police.

R. Ashok, Karnataka’s Home Minister and a senior Bharatiya Janata Party leader, said the explosion was a “clear act of terror” which came weeks ahead key state-legislature elections. No one has claimed responsibility for the attack, police said.

Authorities have yet to determine the motive behind the blasts and whether it was a terror attack.

“Only after we investigate further, can we ascertain for sure whether this was a terror attack,” said Bipin Gopalkrishna, director-general for law and order in Karnataka.