Two people arrested in connection with a grenade attack on Zoo Road in Guwahati were sent to 10 days in police custody on Friday, ANI reported. The grenade blast on Wednesday had injured 12 people, including two Sashastra Seema Bal personnel.

United Liberation Front of Assam leader Pranamoy Rajguru and television actress Jahnabi Saikia were arrested by the Assam Police on Thursday, The Indian Express reported. The police claimed Rajguru is a “senior cadre” of the ULFA.

Guwahati Police Commissioner Deepak Kumar said Rajguru, who is from Sivasagar, and television actor Jahnavi Saikia were arrested following a police raid at a home they had rented in the city’s Bagharbari locality. Saikia is accused of aiding Rajguru and both allegedly played a key role in planning the attack in which at least 12 people were injured.

“Pranamoy Rajguru is a senior ULFA cadre who joined the outfit in 1986,” News18 quoted Kumar as saying. “Operating under sleeper cells in Guwahati and adjoining areas, he helped the outfit execute their plans, and was assisted by Jahnavi Saikia. They have confessed to the crime, and our investigation will continue. We have come to know their modus operandi behind the blast, but we are trying to find out the greater design behind it.”

Anup Chetia, the leader of the pro-dialogue faction of the militant group, however, denied Rajguru was an active member of his group and said “whosoever was behind the act could not achieve their goals by such acts”. The anti-talks ULFA (Independence) group has claimed responsibility for the grenade explosion.

Kumar said the police have identified at least three other suspects for their alleged role in the explosion, PTI reported. He said a 9 mm pistol, 25 rounds of ammunition, 20 kg of gunpowder and bomb-making equipment were seized during the raid in Bagharbari, IANS reported.

Director General of Police Kuladhar Saikia said the police were interrogating the accused and more arrests would be made. “The investigation is in progress,” he told The Indian Express.

Assam Chief Minister Sarbananda Sonowal promised to arrest and punish those involved in the grenade attack. “Strict instructions have been issued to the DGP [director general of police] in this regard,” he added.