A multi-storey department store has collapsed in the capital of Ghana, Accra, trapping dozens of people in the rubble.

Rescue efforts are continuing, with officials saying that at least four people died in the Melcom store.

The BBC’s Sammy Darko, who has visited the scene, says 42 people have been pulled out alive.

Ghana’s President John Dramani Mahama said he had suspended his campaign for next month’s election.

The government has declared the area in the city’s Achimota neighbourhood a disaster zone.

Vice-President Kwesi Amissah-Arthur went to the site and co-ordinated rescue efforts at the building, which opened earlier this year.

As night fell, hundreds of rescuers continued to dig through the rubble, amid fears that more people were trapped.

Mr Amissah-Arthur said the building had collapsed shortly before the Melcom store was due to open for business.

Rescue efforts were being hampered by the large crowd that had gathered at the site, he added.

“There’s so much noise that it’s not possible to hear the trapped people asking for help,” Mr Amissah-Arthur said.

In a statement on its Facebook page, Melcom said it had rented the building which housed its Achimota branch on a 10-year lease.

“This is indeed a very tragic incident,” it said.

“We are doing everything possible to see that help reaches those who need it. Our heartfelt condolences and deepest sympathies goes to the families of those who may have lost their lives.”

Our reporter says customers often queue outside the store before it opens and officials say they believe about 50 people may been inside at the time of the collapse.

Eyewitness Ama Okyere told the AFP news agency she was very close to the shopping centre when the building came down.

“I had to run for my life. I was so terrified. I believe there are lots of people trapped under this because this is a heavily patronised shopping mall in the area.”

Family members tried to call relatives feared trapped beneath the rubble on their mobile phones, AFP reported.

Another witness, John Owusu, said he heard a bang before the building collapsed.

President Mahama, in a tweet moments after the building collapsed, said: “My prayers are with the workers, shoppers and others who are trapped in the rubble of the Achimota Melcom building.”

He has cut short his campaign in the north of the country and has flown back to Accra to see the rescue effort.