An explosion damaged the headquarters of the largest party in the Dutch parliament, D66, on Thursday evening, local police said, adding there were no injuries.
Police said a suspect had been arrested following the explosion, which happened at the party office in the center of The Hague shortly after 9 p.m. local time (1900 GMT).
Dutch Prime Minister Rob Jetten, who is also the leader of D66, said a bomb made of fireworks had been thrown through the letterbox in the front door of the building in what he described as "a cowardly act of intimidation."
D66 won in surprise victory
Last year, the centrist, pro-EU D66 party won the election in the Netherlands in a surprise victory over the far-right Freedom Party led by nationalist Geert Wilders.
Its head office was also damaged during an anti-immigration protest last year, when protesters smashed the windows of the party seen by many on the far right as serving a progressive elite.