An explosion hit the centre of the eastern Afghan city of Jalalabad on Sunday, killing at least 19 people, including several members of the small Sikh minority, provincial government officials said.

The blast, hours after President Ashraf Ghani had opened a hospital in Jalalabad, damaged shops and buildings around Mukhaberat square in the city, said governor's spokesman Attaullah Khogyani.

Ghulam Sanayi Stanekzai, police chief of Nangarhar said the explosion was caused by a suicide bomber who targeted a vehicle carrying members of the Sikh minority who were travelling to meet the president.

Officials said at least 10 of the dead were Sikhs.

Afghanistan is an overwhelmingly Muslim nation but a small number of Hindus and Sikhs remain in the country.

Ahead of Ghani visit

Inaamullah Miakhel, a spokesman for the provincial health department of Nangarhar, said 19 people had been killed and 20 wounded.

Officials said the casualty total might have been even higher had much of the city not been blocked off for Ghani's visit. He was not in the area when the blast occurred.

There was no immediate claim of responsibility for the blast, the latest in a series to have hit Jalalabad, the provincial capital of Nangarhar, where Daesh militants have established a strong presence in recent years.

The attack underlined the fragile security situation in Afghanistan after last month's brief ceasefire between government forces and the Taliban.

The three-day truce did not include Daesh, which fights both government forces and the Taliban and which has shown no sign of letting up its campaign of violence.