The sudden mysterious death of Makueni Senator Mutula Kilonzo might have been linked to the ICC case involving President Uhuru Kenyatta and Deputy President William Ruto, his son has said.

Several months to his death, the lawmaker had sounded an alarm – even in Parliament - about threats to his life because he was outspoken that ICC suspects should face the court.

The senator's family has for the first time revealed ICC prosecutor Luis Moreno Ocampo had sent a letter to Kilonzo seeking a statement about the 2007-08 post-election violence.

The senator's son, Makueni Senator Mutula Kilonzo Jnr, told the Star on Tuesday that despite their suspicions, the family cannot conclusivly say the death was linked to the ICC cases.

“I can’t tell whether there was a link. I found a letter written to him by ICC Prosecutor Luis Ocampo seeking a statement on the post-election violence."

But he made an impassioned plea to Senate on Monday not to ignore three arrested Senators who opposed the government's revenue sharing forumula and refused to play ball.

“I was elected in this Senate because one person who was a member of this House was found dead on his bed…if it is not the three, it will be me or you [meaning Senate Speaker Kenneth Lusaka],” he said.

Police had detained, then released opponents of the formula - Senators Christopher Lang’at (Bomet), Steve Lelegwe (Samburu) and Cleophas Malala (Kakamega). Their absence threw voting into disarray.

Senator Mutula was found dead in bed at his Kwa Kyelu ranch in Machakos county. His family said he had been forced to ingest an overdose of blood pressure tablets and carbonated water, which killed him.

While at the Justice ministry, Kilonzo was vocal and adamant that Kenyans facing charges in connection with the post-election violence should cooperate with the Hague-based court.

Even while at the Education ministry, he complained that anonymous people kept sending him threatening messages, telling him to be silent. He said they invoked instructions from 'faceless bosses', his family said.

On Monday Kilonzo Jnr warned the Senate not to ignore the rebel Senators. Worse could happen, he suggested.

At the ICC, President Kenyatta (then Gatundu South MP), DP Ruto (then MP Eldoret North), former Head of Civil Service Francis Muthaura, Radio journalist Joshua Sang, former ODM chairman Felix Kosgey, and ex-police boss Hussein Ali were then set to face the court.

They were charged with orchestrating crimes against humanity in the violence that rocked the country. The trials never took off as the cases collapsed for lack of evidence.

A number of prosecution witnesses recanted their statements to investigators, some disappeared, some died under mysterious circumstances. The cases fell apart as the President and DP reviled the 'foreign court. They portrayed themselves as victims and won election in 2013.

- The Star