Samburu Senator Steve Lelegwe was on Monday night released after being questioned by detectives at Maralal police station.
Lelegwe was expected at the Senate to vote for the revenue sharing formula.
Earlier, Bomet Senator Christopher Langat was freed after being questioned at Bomet police station.
The senator said that he was accused of grouping 200 youths on August 12 for an oath at a local river, an allegation he denied.
Meanwhile, hundreds of residents led by some MCAs stood outside Maralal police station as Lelegwe was escorted by DCI officers to an office at Maralal police station for questioning.
Ndoto MCA Raisy Letura accused the government of intimidating senators opposed to proposed county revenue sharing formula.
“People in this country cannot stand such kind of intimidation. Senator Lelegwe is a clean senator, we know he has no criminal record and we know today he is being harassed because the government wants him to vote on that formula, a move that is backward and cannot be appreciated in any democratic country,” he said.
Letura said residents and leaders are fully behind their senator.
Samburu assembly Leader of Majority at Samburu Christopher Lentukunye said his supporters will wait for him until the questioning is over.
“I'm here with residents of Samburu and my fellow MCAs just to see what government and police are asking our senator,” he said.
