One freed, four to present defence over Kenya university attack

The five suspects went on trial in January 2016 for their involvement in the deadly attack at Garissa University in northeastern Kenya which was claimed by Somalia's Al-Qaeda-linked Shabaab insurgents.

It was the east African nation's deadliest attack since the 1998 bombing of the US embassy in Nairobi.

Four gunmen involved in the massacre were killed, but five others were prosecuted for terrorism and conspiracy to commit an attack, with 22 witnesses testifying.

Magistrate Francis Andayi ruled on Tuesday that there was no evidence linking one of the men, Osman Abdi Dagane, a Kenyan citizen, to the attack.

However the others, Mohamed Ali Abdikar, Hassan Aden Hassan, Sahal Diriye and Rashid Charles Mberesero -- a Tanzanian national -- will present their defence.

Their next appearance is on February 13.

Earlier this month, Andayi ruled that three suspects have a case to answer for their alleged involvement in an attack on the Westgate shopping mall in Nairobi in 2013 in which 67 people died. One man was acquitted.

Their trial will continue on March 21.

Two weeks ago Kenya was hit by its worst attack since Garissa, when Shabaab gunmen targeted the Dusit hotel and office complex in the capital, killing 21 people.

The Islamist group has targeted Kenya and stepped up recruitment in the country ever since it sent troops into Somalia in 2011.

Just days after the Dusit attack gunmen were foiled trying to strike a Chinese construction site in Garissa, and on Saturday two people were lightly injured in a mysterious explosion in central Nairobi, further setting the country on edge.

This prompted the national police to put out a statement urging the public, transport operators, malls, hotels, places of worship and education, to "step up their level of alertness".