Sri Lankan authorities have requested the public to surrender swords and large knives as part of beefing up security.
At the same time, Police said knives used for everyday activities should not be needed to surrender, reported BBC. In raids, hundreds of weapons have been seized since the 21 April attacks. Sri Lankan President Maithripala Sirisena told Reuters on Saturday that some 25 to 30 people linked to the bombings were still in hide, reported BBC.
In the largest bombing incident in the history of Lanka, more than 250 people had been killed in the serial bombings, which targeted churches and luxury hotels.
In addition to weapons, police spokesman Ruwan Gunasekara called on people in possession of "police or camouflaged military uniforms" to hand them in to their nearest police station on Saturday or Sunday.
"We have already identified all active members of the group and it's a case of now arresting them," he said. The president added that there was "no information yet to say these suspects are suicide bombers."
Authorities in Sri Lanka have blamed the blasts on two previously little-known local Islamist groups - National Thowheed Jamath and Jamathei Millathu Ibraheem - whom they suspect had international links. Mr Sirisena said intelligence services from eight countries were helping Sri Lanka with its investigations.