Investigations into the Uhuru Park grenade attack that killed six people have hit a dead end.
Sources said detectives had not found any useful information beyond the fact that the blasts were set off by three men who walked into the park.
Officers close to the investigation but who cannot be named as they are barred from divulging details on an ongoing probe said detectives have yet to establish the motive of the June 13 attacks, which wounded 131 people.
On Monday, police once again appealed for public help and gave out new telephone numbers, in addition to those they had released last week, through which information can be channelled.
Police have also offered a Sh500,000 bounty to volunteers of information that would lead to the arrest of the attackers.
The grenades exploded at a religious crusade which had been turned into a rally against the proposed constitution.