"An IED (Improvised Explosive Device) that was planted by the roadside near Khuyathong area, close to Imphal market, exploded killing three labourers and wounded four others," a police official said.
He said that the injured have been rushed to the Regional Institute of Medical Science and Hospital. The condition of them is stated to be critical.
Senior police officials along with additional security forces have rushed to the spot and launched a combing operation to nab the people responsible for the incidents.
No militant group has claimed responsibility for the blast as yet.
Manipur Chief Minister O Ibobi Singh has condemned the blast.
This is the third incident of its kind within a span of a month in Manipur.
Two youths were killed and four others injured when unidentified militants triggered a bomb blast in Imphal market Dec 15