Hitting out at Delhi Chief Minister Arvind Kejriwal, Congress Vice-President Rahul Gandhi on Thursday alleged that the Aam Aadmi Party (AAP) leader was "trying to back the perpetrators of the bomb blast in Punjab".

"There was bomb blast a couple of days back in which six people died. And Arvind Kejriwal is backing the perpetrators of the blast. He is allowing them to contest elections. This is very dangerous for Punjab. If these elements gain strength in Punjab, then it will hijack all the development issues," said Gandhi during a public rally, on the last day of campaigning for the February 4 elections.

Two men and a child were killed in the explosion on Tuesday evening just as a rally of Congress candidate Harminder Singh Jassi ended at Maur Mandi town, 200 km from Chandigarh. The death toll went up later as some injured died in hospital.

Gandhi's comments come as Punjab Deputy Chief Minister Sukhbir Singh Badal earlier said in a statement that "the manner in which the bomb blasts were executed was a throwback to the days of terrorism".

Badal said that the blast was a direct result of the AAP's nexus with radical elements.

Earlier, Kejriwal had called for Badal's arrest, alleging that he had a role in the blasts.

"To ensure peaceful elections, Sukhbir Badal should be immediately arrested. His role in yesterday's blast must be probed. He'll cause more violence," Kejriwal had tweeted. 

State Congress president and chief ministerial candidate Amarinder Singh has also accused Kejriwal for "promoting extremist forces" such as the Khalistan Commando Force.

He said that Kejriwal, who had stayed at a KCF extremist's house in Punjab, was fanning terror forces through his actions.

"Even if the AAP is not directly involved in the explosions, it was clearly promoting extremist ideology," he said.

Addressing the rally, Rahul on Thursday also promised to curb the drug menace in Punjab by bringing in new law and also vowed to give treatment to every family in the hospitals.

"If we come to power, we will give free treatment to every family in Punjab. We will also establish a state-of-art cancer hospital in Punjab, which will be well-renowned across the country," he added.