Two Russian embassy staff are among at least six people killed in a suicide bombing in the Afghan capital Kabul, Russian and Taliban officials say.

Guards shot the attacker dead as he approached the entrance to the consular section, officials said.

A number of other people were reported to have been wounded. The Islamic State group said it was behind the attack.

The attack is the first on a foreign mission in Afghanistan since the Taliban swept to power in August 2021.

Earlier, a Taliban official said at least 10 people had been injured. Russia's state-owned news agency RIA reported that a diplomat and an embassy security guard had been wounded.

Other media reports put casualty figures higher. As well as the embassy staff, four Afghans waiting for consular services were killed, police said.

"This morning, an explosion took place at the Russian embassy in Kabul - four people and two employees of the Russian embassy were killed, and a number of Afghans were injured," a statement from the Taliban police chief's spokesman in Kabul said.

It added the suicide bomber had been spotted by Taliban personnel guarding the embassy as he approached people gathered in front of the building.

"He was identified by security and targeted, which caused a blast," the spokesman said.

Russia's foreign ministry said "an unknown militant set off an explosive device near the entrance to the consular section".

"Without any doubt, we are talking about a terrorist act, which is absolutely unacceptable," Kremlin spokesman Dmitry Peskov told reporters in Moscow.

Speaking from the hospital, survivors of the attack spoke of the chaos in its aftermath.

"I went to the Russian embassy to get a visa. We were sitting outside," a man called Faiz Mohammad told Reuters. "The consul came and we showed him our papers, he guided us towards the entrance door of the embassy. Suddenly the blast occurred and I fell on the ground."

Another man called Wahidullah was close by: "I heard a huge blast. Later I didn't understand what happened to me, I just remember the blast threw me out on the street. My hands and legs were not working, then my cousin ran toward me and brought me to this hospital."

Ahmad Samir, a boy who suffered head injuries in the blast, said "there were so many injured people around, everyone was fleeing the site".

Russia is one of the few countries to maintain a diplomatic presence in Afghanistan. Moscow does not officially recognise the Taliban's government - no country does.

However, the two sides have discussed possible Afghan purchases of commodities like wheat, gas and oil from Moscow.

Violence in Afghanistan has greatly declined since the Taliban returned to power - under its 20-year campaign to drive US-led forces from Afghan soil many attacks were carried out by Taliban militants themselves.

However security has been deteriorating in recent months. A string of deadly bomb blasts has mainly targeted mosques and minority communities, many claimed by the militant Islamic State group who see the Taliban as not radical enough.

Last week, a suicide bomber struck one of western Afghanistan's biggest mosques, killing at least 18 people, including an influential imam who supported the Taliban.