Kenyan police have summoned at least six MPs to "shed light" on statements they made over the violence during the campaign for next week's referendum.
The campaign has been marred by violence
Two MPs said people were being trained to cause chaos during the 21 November vote and police wanted more details, spokesman Jaspher Ombati told the BBC.
Over the weekend, there were further clashes between police and stone-throwing youths at rallies.
The draft constitution, to be voted on, has divided the ruling coalition.
Following clashes at a "Yes" rally in the western town of Busia, Vice-President Moody Awori accused Roads Minister Raila Odinga of stirring up trouble.
'False and reckless'
Mr Odinga and his party have joined up with the opposition to campaign against the draft constitution, under the symbol of an orange, saying the president would retain too many powers.
The Daily Nation newspaper reports that the road from Busia to neighbouring Uganda was blocked by burning barricades for more than two hours after the Yes rally under the sign of a banana.
Two MPs from the Yes camp allegedly said they knew of 800 youths being trained to disrupt the poll. They are expected to record statements on Monday.
The cabinet is divided with several ministers part of the "No" campaign
"When leaders make such allegations - serious allegations - we would want them to substantiate [them]," Mr Ombati told the BBC's Network Africa programme.
He said the police would then be in a position to take action against those preparing violence.
The Daily Nation, however, quotes Mr Ombati as criticising the MPs for making "false and reckless allegations".
Four MPs from the "No" campaign are also expected to present themselves to police after referring to plots to kill "No" leaders.
But one of them, Paul Sang, reportedly told the Nation that he would not go unless he was notified in writing.
"How are we sure that the summons are official? They should do it in writing so that I can engage my lawyer."
If the new constitution is approved on 21 November, it would be the first major overhaul of Kenya's constitution since independence from Britain in 1963.