Mombasa Governor Hassan Joho called on Muslims to unite and help the needy as the Holy Month of Ramadhan started.
Hundreds of faithful started fasting on Thursday after Chief Kadhi Sheikh Ahmed Muhdhar and other religious leaders sighted the moon at 6.35pm in Mombasa on Wednesday.
The Chief Kadhi also called on Inspector-General of Police Joseph Boinett to enhance security in areas the faithful will be going to for night prayers.
"More police officers should be deployed to secure all areas, especially where Muslims go for special prayers at night. I urge all Muslims to pray more during this holy period," Sheikh Muhdhar said.
Mombasa police boss Johnston Ipara said security had been beefed up in the tourist hub and assured Muslims there was no cause for alarm.
Speaking after the Dhuhur prayers at the Ummu Khulthum in Kizingo, Governor Joho asked Muslims to dedicate more time to the cause of Ramadhan.
The governor also urged faithful to pray, unite and forgive one another.
He said Ramadhan was a time for prayers, giving, forgiving others and uniting.
On Wednesday, President Uhuru Kenyatta and Nasa leader Raila Odinga called for unity and forgiveness as they wished the Muslims well during the fasting period.
President Kenyatta said: "On behalf of the people and the government, it gives me great pleasure to send this message of warm greetings, best wishes and solidarity to our Muslim brothers and sisters as they commence the Holy month of Ramadhan."
Mr Odinga said: "I pray that this season reminds us that we are one Kenyan family that ought to stand together in rejection of the forces that seek to divide us. We must stand together in celebration of our common humanity."
In Tana River, Muslim clerics appealed to the national government and NGOs to donate food and clothes to the families displaced by floods.
Winnie Atieno, Abdulrahman Sheriff, Wachira Mwangi, Stephen Oduor and Kalume Kazungu