Belfast, Northern Ireland (CNN) -- The dissident republican group the Real IRA claimed responsibility Tuesday for a car bomb that exploded outside a bank in Londonderry, Northern Ireland, wounding two police officers and causing "substantial damage" to the bank, police said.
The claim was made in a call to the Derry Journal, the newspaper reported. A representative for the organization, using a recognised codeword, said it was behind the attack.
The two officers were hurt when they were blown over by the force of the blast, police Chief Superintendent Stephen Martin said. They suffered neck and ear injuries, he said.
The incident happened just after midnight near the bank and a shopping center on Culmore Road, the Police Service of Northern Ireland said.
Police said they had received a warning about an hour before the explosion and had set up a cordon before the bomb went off.
The bomb damaged the windows on all levels of the four-story Ulster Bank, which is near a major intersection where a McDonald's restaurant and Ramada hotel are also located. Houses and a home for the elderly are also nearby and had to be evacuated ahead of the blast, officials said.
Martin said either the bank or the hotel may have been the target, but police were also investigating whether the device was abandoned because of a security presence.
The explosion came three weeks after the Real IRA warned it would begin targeting banks and bankers.
"The role of bankers and the institutions they serve in financing Britain's colonial and capitalist system has not gone unnoticed," the group told The Guardian, in what the British newspaper said was a series of written answers to questions it had posed to the Real IRA's leaders.
"Let's not forget that the bankers are the next-door neighbors of the politicians," the group told the paper. "Most people can see the picture: The bankers grease the politicians' palms, the politicians bail out the bankers with public funds, the bankers pay themselves fat bonuses and loan the money back to the public with interest. It's essentially a crime spree that benefits a social elite at the expense of many millions of victims."
The bombing will be damaging to the city, Martin said. Tourists from the United States and Japan were in the hotel when police received news of the bomb, he said.
Former U.S. President Bill Clinton was in Londonderry last week to promote investment and job creation, and Martin said the bombers had given their response -- that they want to destroy jobs.
Journalist Peter Taggart contributed to this report.