A stun grenade has been thrown and shots have been fired into the residential compound of prominent Kenyan opposition politician Kalonzo Musyoka, police say.
No one was was injured in the attack on Wednesday night, and the motive was still unclear.
Mr Musyoka is the deputy leader of the National Super Alliance (Nasa), and was the running mate of its presidential candidate, Raila Odinga, in last year’s disputed election.
He has been at the centre of controversy attend failing to attend a “swearing-in” organised by Mr Odinga on Tuesday, where he declared himself the “people’s president” after boycotting an election-run won by President Uhuru Kenyatta.
Mr Musyoka would be “inaugurated” as his deputy at a late date, Mr Odinga said.
His absence fuelled speculation of a split within NASA.