A police brigadier general was killed when a bomb exploded under his car on Wednesday, security officials said, in the fifth such targeted attack in Egypt's capital within a week.
The blast in the upscale western suburb of October 6 killed Ahmed Zaki, a commander of Egypt's central security forces who have spearheaded a crackdown on supporters of ousted Islamist president Mohamed Morsi.
A little-known jihadist group, Ajnad Misr (Soldiers of Egypt), said in a statement on Facebook and Twitter that it had killed Zaki.
The group has claimed several attacks on police in Cairo, and had warned of further retaliation for the crackdown on Islamists who back Morsi.
Militants have launched scores of attacks mainly targeting security forces since the military deposed Morsi last July after massive protests calling for his resignation.
The general was fatally wounded as he headed for work, security officials said, adding that two conscripts were wounded in the attack.
Video footage posted on newspaper websites showed the front of the car destroyed. It was painted light green, not the usual dark blue of police vehicles.
Police officers are increasingly having their cars repainted to avoid being easily identified by militants and targeted.
Zaki was the third senior police officer to be killed in Cairo since the start of the year. Three other police have been killed in four more attacks over the past week.
Prime minister Ibrahim Mahlab and interior minister Mohamed Ibrahim attended his funeral later on Wednesday.
In the Mediterranean city of Alexandria, meanwhile, a police lieutenant was killed in a gunfight with wanted "terrorist elements", security officials said.
Signup to our newsletter and follow us on Facebook and Twitter!
They said one "terrorist" was killed and another wounded, adding that police retrieved an explosives-laden belt and two home-made bombs.
- Police feared for decades -
Egypt's police force, feared for decades, stirred public outrage over its brutality and deadly tactics during the 2011 uprising which toppled veteran president Hosni Mubarak.
It has rehabilitated itself in public eyes by pursuing supporters of the unpopular Morsi after his ouster, but has at the same time incurred the wrath of militants.
Most of the deadliest attacks in Cairo and elsewhere, including in the restive Sinai Peninsula, have been claimed by Ansar Beit al-Maqdis (Partisans of Jerusalem), a jihadist group inspired by Al-Qaeda.
The interior ministry said the police lieutenant targeted in Alexandria on Wednesday was killed by members of Ansar Beit al-Maqdis.
Official figures show that about 500 people -- mostly police officers and soldiers -- have been killed in gun and bomb attacks by militants since Morsi's ouster.
Amnesty International, meanwhile, says that more than 1,400 people have been killed in the police crackdown on Morsi supporters.
More than 15,000 Islamists, mostly from Morsi's Muslim Brotherhood, have been jailed, while hundreds have been condemned to death after often speedy trials.
Morsi was ousted by his army chief, Abdel Fattah al-Sisi, who is now the frontrunner in a presidential election next month.
The 59-year-old Sisi has been riding a wave of popularity after ousting Morsi. Leftist leader Hamdeen Sabbahi is his only declared rival so far in the May 26-27 vote.