Gunmen in Egypt boarded a bus carrying Palestinians from Cairo to Gaza and seized four of the passengers before letting the others continue, Hamas officials in the strip said early Thursday.

Interior ministry spokesman Iyad Bezem said in a statement that the kidnapping took place late Wednesday night in the troubled northern Sinai region as the bus headed for the Rafah border crossing into Gaza.

A powerful car bomb blast tore through a Cairo police building Thursday injuring at least 29 people in the latest attack claimed by the Islamic State group against Egyptian security forces.

Six policemen were among those wounded in the explosion but officials said none of the injuries were life-threatening.

The United States denounced Egypt's newly expanded counterterrorism law Tuesday, expressing concern about its potential impact on human rights in the country, a military ally of the U.S.

President Abdel Fattah al-Sisi signed a law Sunday that would expand the government's surveillance powers and, according to critics, muzzle dissent and target critics.

Egypt hit back Saturday at a call by Human Rights Watch for an international investigation into the killing of hundreds of protesters in Cairo by security forces two years ago.

The foreign ministry criticised the New York-based watchdog's report on the deaths of supporters of ousted Islamist president Mohamed Morsi in Rabaa al-Adawiya Square as "politicised and lacking objectivity".

A Croatian hostage whom the Islamic State group claims to have beheaded is thought to have been kidnapped by a criminal gang in Egypt before being turned over to the jihadists, Croatia's foreign minister said Thursday.

Tomislav Salopek, a 31-year-old father of two working for a French engineering company, was seized last month from a car some 22 kilometers (14 miles) west of Cairo.

The Islamic State group said Wednesday it has beheaded a Croatian hostage, and released a picture of a body after what would be the first such killing of a Westerner in Egypt.

Croatian Prime Minister Zoran Milanovic told reporters he could not "confirm with 100 percent certainty" that Tomislav Salopek, who worked for French company CGG, had been murdered.

A small bomb exploded Monday near a traffic post in the Egyptian capital wounding four policemen, two of them seriously, in an attack claimed by a Cairo-based militant group.

Jihadists have launched a wave of attacks targeting security forces since the ouster of Islamist president Mohamed Morsi in 2013. 

Twenty-one people have died and 66 others were hospitalized with exhaustion as soaring temperatures and high humidity hit Cairo and other parts of Egypt, the health ministry said Monday.

The victims, who all died on Sunday, succumbed as temperatures reached highs of 47 degrees Celsius (117 Fahrenheit), in conditions made less bearable by elevated humidity levels.

U.S. Secretary of State John Kerry flew to Egypt on Saturday to relaunch a strategic partnership with Washington's longtime ally, at the start of a regional mini-tour, a correspondent said.

He is also due in Qatar on Monday to meet his Arab counterparts in the Gulf to try to ease their concerns over the Iran nuclear deal.

Officials close to Prime Minister Tammam Salam were not optimistic on Wednesday on a possible solution to Lebanon's political crisis as top diplomats rushed to his support to stop a possible resignation decision.

The officials, who were not identified, told al-Joumhouria daily that “all efforts, which had been exerted until Tuesday, hit a dead-end as a result of inflexible stances that caused a failure in coming up with solutions” to controversial issues.