The Kenya African National Union (KANU) Secretary General George Wainaina was last evening arrested over the cold blood murder of lawyer Mathew Kyalo Mbobu.
The role Wainaina played in the murder is not yet clear.
Sources said he was among six people who were detained as suspects in the murder.
A substantial amount of money was recovered from the homes of the suspects by teams of the police pursuing the matter.
The team had to bring in money counting machines to help in the process as part of the probe.
The exercise was conducted at Nairobi Area where part of the team investigating the murder is based.
“They are in custody as suspects. They are alleging to be friends though,” said an official aware of the probe and the developments so far.
The killer weapon and killers are yet to be found, police said.
The suspects included those he met at the restaurant on Tuesday afternoon hours before his murder.
Police said they were looking for more people they deem persons of interest to be interrogated and reveal the nature of the meeting they had with Mbobu at Sagret hotel