The Kano State Command of the Nigeria Police Force has said a gas cylinder, and not a bomb, exploded in the Sabon Gari area of the state on Tuesday.
Samaila Shuaibu Diko, the Commissioner of Police, said the explosion occurred at a welding shop adjacent to the primary school on Aba Road.
He said four persons died in the explosion which brought down the building while others sustained injuries.
Diko said some people are still trapped under the rubble.
The incident has led to pandemonium in the area as shop owners hurriedly closed their stores and fled the area.
SaharaReporters had earlier today reported that an early morning explosion at Aba Road, Sabon Gari, threw the residents into confusion.
The incident was said to have occurred near a private school identified as Fimbal Royal Schools.
Gory images and videos of victims have flooded the microblogging platform, Twitter.
The National Emergency Management Agency has yet to make an official statement.