At least two people have been killed and six others wounded in two explosions in Manila, capital of the Philippines, a police spokesman said.

The first blast occurred around 6pm (10:00 GMT) on Saturday near a mosque in Quiapo, one of the older parts of Manila, killing two and wounding four others, according to city police chief Oscar Albayalde.

Two and a half hours later, a second blast hit the same area – a narrow street crammed with stalls hawking clothes and homeware – wounding two policemen inspecting the site, according to a photographer for the AFP news agency, who witnessed the explosion.

The police chief suggested that gangs could be to blame.

"We do not see any indication that this is a terror attack," he said, and added: "We do not want to speculate, but it's possible this is a gang war."

Albayalde said the first blast appeared to have come from a package that was being delivered by a man on a motorcycle.

"The man on the motorcycle who delivered the package was killed. The other killed was the person who received the package," he told the DZRH radio station.

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The explosions occurred near an Islamic community centre and about a hundred metres from the Quiapo Golden Mosque, damaging part of the Islamic centre and shattering windows in nearby buildings.

"It was very powerful," Omar Yahya, 22, who was at the Islamic centre when the first explosion hit, told the AFP. "Windows were broken and the wooden part of the building collapsed".

Manila was also hit by an explosion last week. At least 14 people were wounded on April 28 when a home-made pipe bomb was detonated in the district of Quiapo.

That attack occurred as Southeast Asian leaders were meeting for a summit a few kilometres away.

The Islamic State of Iraq and Levant (ISIL) group claimed responsibility for the explosion on April 28, but police blamed it on a gang fight. One person was arrested over that attack.