The Uttar Pradesh Police on Sunday said they had busted an Al Qaeda unit in Lucknow, which was reportedly planning suicide attacks in crowded areas of the city and other places in the state.

Two men named Minaz Ahmad and Masiruddin, also known as Mushir, both residents of Lucknow, have been arrested as part of the operation, the police said, as per a report by ndtv.com.

"ATS (Anti-Terrorism Squad) UP has uncovered a big terror module. The team has arrested two terrorists linked with Al Qaeda's Ansar Ghazwat-ul-Hind. Cache of arms, explosive materials have been recovered," senior police officer Prashant Kumar was quoted as saying by the media organisation.

The two suspects were detained from Kakori town in Lucknow district after searches were conducted, the police said.

In a related incident in Bengal, three suspected terrorists of Jamaat-ul-Mujahideen Bangladesh (JMB) were arrested from south Calcutta's Haridevpur area on Sunday afternoon, police said.

The arrests were made by the Calcutta Police's Special Task Force (STF), they said.

The three suspected JMB terrorists were living in a rented accommodation for a few months in the middle-class locality, raising concern among the locals.

The three suspected terrorists were nabbed following a tip-off, a senior police officer said.

"We are investigating the matter and interrogating them. It is at a very initial stage," the officer told PTI.