LUCKNOW, May 22: At least four people were injured in three bomb blasts which went off in rapid succession in the northern Indian city of Gorakhpur on Tuesday, officials said.

“These blasts appeared to have been caused by crude bombs,” city police spokesman Avinash Mishra told AFP by telephone from Gorakhpur.

The devices were concealed on three bicycles used for the attacks, a top-level official said in Lucknow, capital of Uttar

Pradesh state where Gorakhpur is located.

“These crude bombs were kept in tiffin (lunch) boxes in these three brand-new bicycles,” said state Home Secretary K. Chandramouli, ruling out the involvement of India’s various militant groups.

“This appears to be the work of some mischief-mongers,” he said without elaborating. He added a `high alert’ had been sounded across Uttar Pradesh, India’s most populous state where a new government was voted in this month.—AFP