Four family members of ULFA central publicity secretary Mithinga Daimary alias Deepak Das -- mother Phuleswari, wife Rupjyoti, sister Latika and brother Dharani -- were killed at Barama village, an ULFA stronghold in Nalbari district last night, officials said today.

The former ULFA members, in a revenge killing, also shot dead ULFA chairman Arabinda Rajkhowa's brother, Dimpo, an Assam State Transport Corporation supervisor before the ASTC's depot in Dibrugarh town yesterday, sources said.

In another incident, they also kidnapped and killed an Oil India employee H P Misra, younger brother of ULFA activist Munna Misra, at Duliajan in Upper Assam yesterday.

Local media reports today claimed that the surrendered militants had decided to attack the ULFA in retaliation for the killing of several of theircadres in the recent past.

Meanwhile, armed National Democratic Front of Bodoland (NDFB) militants stormed into a house in Subhaspalli village in Darrang district and gunned down four members of a family, including two women before attacking other houses, leaving eight injured yesterday.

Meanwhile, the blaze in the Indian Oil Corporation's depot at Thekeraguri in Nagaon, for which the ULFA had claimed responsibility was brought under control last night.