At least 45 protesters have been shot dead in the Yemen capital of Sanaa after unidentified gunmen opened fire from rooftops overlooking the central square.

The incident, which also left 270 injured and was described by opposition leaders as a ‘massacre’, was condemned by the international community.

President Ali Abdullah Saleh denied that the police or armed forces were behind the attack and declared a national state of emergency.

However, the BBC reported that many people in Yemen are seeing the move as a way to suppress protesters and block media coverage in the country.

The escalating violence in Yemen is making it increasingly unlikely that a compromise will be reached between President Saleh and opposition parties.