An explosive device was thrown at a political event in a western port city, but police say Japanese Prime Minister Fumio Kishida was unharmed and was able to leave without incident.

On Saturday, Kishida travelled to the Saikazaki port in the Wakayama prefecture to support the candidate of his ruling party in a local election.

The explosion happened right before he was about to start speaking.

Witnesses say a suspect was pulled to the ground by police as terrified onlookers ran for safety and smoke filled the air.

Hardly nine months have passed since the assassination of former Japanese Prime Minister Shinzo Abe as he gave a campaign address in the western city of Nara.

A later inquiry revealed gaps in Abe’s security after the assassination stunned the country.

After Saturday’s explosion, Kishida addressed a crowd in another location, saying the incident should not disrupt the electoral process.