A crude bomb was hurled at the BJP office here, but there was no casualty, police said on Wednesday.
The incident occurred at around midnight.
Glass panes of the main entrance door were damaged in the incident, Thiruvananthapuram city police commissioner, S Sparjan Kumar told PTI.
There were 3 to 4 BJP workers on the top floor of the office when the crude bomb was hurled, but none were injured.