WSWS claims that it is possible that the attack was carried out by the LTTE in retaliation to a bomb blast targeting a van on May 23 in LTTE controlled area, which they (the LTTE) claimed to be carried out by the Sri Lankan military.
June 4, 2008 a bomb exploded between the railway tracks hit by packed commuter train at 0710 local time between the Dehiwala and Wellawatte railway stations on the same rail line, injured at least 24 civilians.