Kenyan police have taken necessary security steps following the abduction of two Cuban doctors in the northeast border town of Mandera last week, a senior police officer said Thursday.

Inspector General of Police Hilary Mutyambai also said there was no cause for alarm following Wednesday's alert on imminent terrorist attack at the country's Jomo Kenyatta International Airport (JKIA).

"I wish to assure the country that there is no cause for alarm. All necessary security steps have been taken," Mutyambai told journalists in Nairobi.

Jomo Kenyatta International Airport was on Wednesday temporarily closed following a bomb scare in one of Kenya Airways' planes bound for South Africa.

The police said a passenger who was arrested mentioned the word bomb in an argument, making passengers panic as the plane was taxing ready for take-off.

But the police chief said the country is secure and security agencies through multi-agency security management system is monitoring and managing security appropriately.

The police chief's remark also came after the Kenya Airports Authority received intelligence that al-Shabab terror group was planning to attack airports during the Easter holiday.

The intelligence brief indicated that the terror group has dispatched four attackers with improvised explosive devices which were to be delivered to four of its operatives in Garissa County in northeast Kenya.

"The smuggled IEDs are small, round and magnetic and are intended to be attached to vehicles. Measures shall include screening for both persons and vehicles using Explosives Trace Detectors where available, explosive canines where available, random searches, enhanced patrols within public areas," KAA said.

The alert, which has already shared with various security operatives, says that the explosives maybe snuggled into other major towns and crowded places.