A bomb exploded close to the foreign ministry in Cairo on Sunday killing at least three policemen and injuring six other people, in what Egyptian state television said was an attack on a police checkpoint using a “primitive device”.
The attack, by suspected Islamic militants on a busy Nile-side street, is the latest in a string of bombings and shootings targeting the Egyptian security services.
Scores of police and army personnel have been killed in similar incidents mostly in the troubled Sinai peninsula since last year’s military overthrow of Mohamed Morsi, the elected Islamist president.
A Sinai-based group called Ansar Beit al Maqdis has claimed responsibility for attacks mainly in the Sinai but also elsewhere in Egypt including the bombing early this year of the police headquarters in Cairo. It says it is avenging the killing of hundreds of supporters of Mr Morsi and his Muslim Brotherhood group in a government crackdown since the toppling of the former president.
Over the past year there have been frequent reports of home-made bombs found and defused by police in busy locations in Cairo including metro stations.
The army and police have been conducting a joint campaign against villages in northern Sinai near the border with Gaza, which are strongholds of the ABM. In the latest incident earlier this week a roadside bomb killed five conscripts travelling in an armoured convoy.
Reports from the Sinai say civilians have been caught up in the violence with ABM decapitating several people it accused of collaborating with police. For their part, the security services have destroyed homes and killed locals during raids against villages where the militants are suspected to have taken refuge.
Sunday’s Cairo bombing also comes as Egypt finds itself drawn into several regional conflicts. It has been encouraged to endorse the wide-ranging coalition taking on the Islamic State of Iraq and the Levant, the group known as Isis, which has built contacts with Egyptian militant groups in the Sinai Peninsula.
The Egyptian government has been accused by US officials and Libyan Islamists of collaborating with the United Arab Emirates and Libyan liberals in launching air strikes on the positions of militia groups opposed to the elected government now seeking refuge in the eastern Libyan city of Tubruq.
Abdel Fattah al Sisi, the president, told the Associated Press on Saturday that Egypt would support the US-led war against Isis, though he appeared to rule out sending troops.
"We are completely committed to giving support. We will do whatever is required," he said. He suggested that his ousting of the Brotherhood president last year was an early move against militancy aimed at pre-empting a civil war in the country similar to the conflicts raging in Syria and Iraq.
The Egyptian authorities have labelled the Brotherhood a terrorist organisation, and Mr Sisi has accused it of being a front for groups like ABM – something that the Brotherhood, which has a strong record of winning elections, vehemently denies.