MINA, Saudi Arabia — In sweltering temperatures, Muslim pilgrims in the Saudi city of Mecca converged on a vast desert tent camp Friday, officially starting the annual Hajj pilgrimage. Earlier, they circled the cube-shaped Kaaba in the Grand Mosque, Islam’s holiest site.

More than 1.5 million pilgrims from around the world have already amassed in and around Mecca for the Hajj, and the number was still growing as more pilgrims from inside Saudi Arabia joined. Authorities expected the number to exceed 2 million this year.

This year’s Hajj comes against the backdrop of the raging Israel-Hamas war in the Gaza Strip, which pushed the Middle East to the brink of a wider conflict.

Palestinians in Gaza were not able to travel to Mecca this year because of the closure of the Rafah crossing in May, when Israel expanded its ground offensive to the coastal strip’s southern city of Rafah, on the border with Egypt.

“We pray for the Muslims, for our country and people, for all the Muslim world, especially for the Palestinian people,” Mohammed Rafeeq, an Indian pilgrim, said as he headed to the tent camp in Mina.

Saudi authorities have apparently been concerned about potential protests against the war during the Hajj pilgrimage. They said they won’t tolerate politicizing the pilgrimage.

“The kingdom resolutely confirms that it will not allow any attempt to turn the sacred sites (in Mecca) into an arena for mob chanting,” Col. Talal Al-Shalhoub, a spokesman for the Interior Ministry, said in a news conference Friday. “The security and safety of the guests of Rahman is a red line.”

Officials said 4,200 pilgrims from the occupied West Bank went to the Hajj. Saudi authorities said 1,000 more from the families of Palestinians killed or wounded in Gaza also arrived, at the invitation of Saudi King Salman.

The invitees were already outside Gaza — mostly in Egypt — before the closure of the Rafah border crossing.

“We are deprived of (performing) the Hajj because the crossing is closed, and because of the raging wars and destruction,” said Amna Abu Mutlaq, a 75-year-old Palestinian woman in Gaza’s southern city of Khan Younis who had planned to make the pilgrimage this year but was unable to.

This year’s Hajj also saw Syrian pilgrims traveling to Mecca on direct flights from Damascus for the first time in more than a decade. The change is part of an ongoing thaw in relations between Saudi Arabia and conflict-stricken Syria. Syrians in rebel-held areas used to cross the border into neighboring Turkey to travel from there to the Hajj.

The Hajj is one of the five pillars of Islam, and all Muslims are required to make it at least once in their lives if they are physically and financially able to do so. It is a moving spiritual experience for pilgrims who believe it absolves sins and brings them closer to God.

It’s also a chance to pray for peace in many conflict-stricken Arab and Muslim countries.