Kenyan police have arrested two men they say had explosives that were to be used in an attack.

The arrests took place Monday in the port city of Mombasa, where police said they found two homemade bombs and a mobile phone that could have been used as a detonator.

They did not give a specific location for a planned attack.

Police said the men were of Somali origin, and Mombasa police chief Robert Kitur told Reuters they suspect the men are linked to the Islamist militant group al-Shabab.

Kenya sent forces into Somalia in 2011 to help the country fight the al-Qaida-linked militant group after al-Shabab carried out a series of bombings and kidnapping in Kenya.

Al-Shabab at one point controlled large parts of Somalia, but was pushed out of major cities by African Union forces and the Somali government. Shabab militants have continued to carry out attacks.