At least eight people were killed and 26 injured after a central Nigeria's electoral commission office in Niger State was hit by an explosion one day ahead of the planned parliament election on Saturday.

The Police Public Relations Officer of the state Police Command Richard Oguche confirmed the incident in Suleja, saying that eight persons died and 26 others injured.

He said the police were investigating the incident.

Nigerian President Goodluck Jonathan confirmed the deadly explosion at the electoral office hours later and ordered an immediate increase in security on the eve of parliamentary polls.

In a separate incident, gunmen attacked a police station where electoral officials were storing vote materials in northeastern Nigeria, killing four.