A wave of suicide bombings hit three Saudi Arabian cities over a 24-hour period. The attacks came on the heels of massive jihadi assaults in the Muslim world last week.

The deadliest occurred in Medina, where four people were killed and another person was wounded, according to an official with knowledge of the event. The city is a major spot in Islam because that’s where Prophet Mohammed is buried.

The bomber, who died in the explosion, targeted security officers, but it is unknown precisely who was killed, the source said.

In Qatif in eastern Saudi Arabia, a suicide bomber attempted to launch an attack at a Shiite mosque but failed, killing himself in the process, according to an official with knowledge of the event. There were no injuries.

Near the U.S. Consulate in Jeddah, a suicide bomber killed only himself after detonating an explosive according to the state-run Saudi Press Agency. Policemen were injured in the attack.

There were no initial claims of responsibility.

Attackers launched strikes last week in Turkey, Bangladesh, Yemen and Iraq, killing scores of people. They are claimed or thought to be carried out by ISIS.

The strikes come as the Muslim holy month of Ramadan ends and Americans celebrate the Fourth of July, their independence day.

Jeddah blast occurs near consulate wall

Early Monday, the Saudi police became suspicious of a man who appeared to be roaming around a parking lot of a major hospital, the news agency reported. When officers approached him, the man detonated what appeared to be an explosive belt.

The explosion happened roughly 33 feet (10 meters) from the consulate’s wall.

Witnesses told CNN the blast occurred about 3 a.m. local time and that it appeared that at least two police officers were slightly injured in the attack.

The Saudi news agency reported that the policemen were slightly injured and that they were taken to the hospital. The report did not specify how many were hurt.

None of the bystanders in the parking lot were injured in the attack, according to SPA.

Police found three devices inside the bomber’s car. A bomb disposal unit used a robot to detonate them, said a journalist who was on the scene.

The Saudi Interior Ministry is investigating the case, according to the SPA.

A U.S. State Department official told CNN that all chief of mission personnel were accounted for. The bombing came after a week of attacks in Turkey, Bangladesh and Iraq, which have left many on edge.

In 2004, the U.S. consulate in Jeddah was attacked by gunmen linked to al Qaeda, who killed five employees.