A fuel tanker has exploded during an attack on a northern Syrian town, killing at least 40 civilians, according to Turkey's Defence Ministry.

Key points: Many victims were burned to death, Syrian activists say

Many victims were burned to death, Syrian activists say The death toll could rise because some of the injured are in a critical condition

The death toll could rise because some of the injured are in a critical condition The attack is being blamed on Syrian Kurdish fighters

The ministry said the attack took place in a crowded street in Afrin, a town controlled by Turkish-backed opposition fighters, and the dead included 11 children.

It said 47 people were injured.

Turkey's state news agency cited unnamed security officials who said the attack was believed to have been carried out by Syrian Kurdish fighters linked to Kurdish militants fighting Turkey.

Turkey and allied Syrian fighters took control of Afrin in 2018 in a military operation that expelled local Kurdish fighters and displaced thousands of Kurdish residents.

The Turkish Government considers the Kurdish fighters who were in control of Afrin to be terrorists. Since then, there has been a series of attacks on Turkish targets in the area.

The Britain-based Syrian Observatory for Human Rights said the blast took place in a market.

Several cars and shops caught fire.

Syrian activists said several people burned to death, including some who were stuck inside their vehicles.

Similar blasts in areas controlled by Turkey-backed opposition fighters have killed scores of people in recent months, attacks that the Government blames on Kurdish fighters.

Turkey supports the Syrian opposition in the war against President Bashar al-Assad but has joined with Russia to secure and monitor local ceasefires.

Activist collectives in northern Syria urged people in the Afrin area to donate blood.

Activists and the Syrian Observatory for Human Rights said the death toll could rise because some of the injured were in critical condition.

AP