Pope Benedict XVI said he was "deeply sorry" in a personal apology made Sunday to Muslims who were upset by his use of a quotation that called some Islamic teachings on holy war "evil and inhuman."

A day earlier, the Vatican's secretary of state issued a statement saying the Pope sincerely regretted that Muslims were offended by his comments — but many Muslim leaders in the Middle East and Asia had condemned the statement as insufficient, demanding a personal apology from the Roman Catholic leader.

On Sunday, in the Pope's first public appearance since he made the controversial comments, Benedict said the text he quoted during a university lecture in Germany on Sept. 12 did not reflect his personal opinion.

"At this time, I wish also to add that I am deeply sorry for the reactions in some countries to a few passages of my address at the University of Regensburg, which were considered offensive to the sensibility of Muslims," the Pope said as he gave his weekly Angelus prayer at his summer retreat in Castel Gandolfo south of Rome.

"I hope that this serves to appease hearts and to clarify the true meaning of my address, which in its totality was and is an invitation to frank and sincere dialogue, with great mutual respect," Benedict said.

The Pope sparked the controversy when, in a speech to professors, he cited the words of a 14th-century Byzantine emperor who characterized some of the teachings of the Prophet Muhammad, Islam's founder, as "evil and inhuman, such as his command to spread by the sword the faith he preached."

Security was high at the Pope's summer palace on Sunday. Police patted down many of the faithful, confiscating umbrellas with metal tips and bottles of liquids from pilgrims waiting to see Benedict.

Sharpshooters kept watch from a balcony and other officers, dressed like tourists, monitored the crowd with video cameras.

Churches torched in Gaza, West Bank

The Pope's earlier comments had sparked unrest in some parts of the world.

Morocco recalled its ambassador to the Vatican to protest the "offensive" remarks, and Indonesian President Susilo Bambang Yudhoyono described the Pope's reference as "unwise and inappropriate," the Kompas daily reported.

On Saturday, Palestinian Muslims firebombed two churches and shot at five others in the West Bank and Gaza Strip to protest against the Pope's comments, sparking concerns of a rift between Palestinian Muslims and Christians.

In the town of Tulkarem, a church built 170 years earlier was torched before dawn and its interior was destroyed, local Christian officials said. In the village of Tubas, a small church was attacked with firebombs and partially burned, Christians said. Neither church is Catholic, the officials said.

On Sunday, gunmen shot and killed an Italian nun at a children's hospital in the Somalia's capital, Mogadishu, in an attack that some witnesses said was retaliation for the Pope's comments.

Some Muslim leaders accept apology

Some Muslim leaders said they accepted the Pope's personal apology.

Senior Muslim clerics in India said it would "help in building good relations between Muslims and Christians" and asked their supporters to call off planned protests.

Turkey's foreign minister said the Pope was still expected to visit in November in what would be his first trip to a Muslim nation.

"From our point of view, there is no change," Foreign Minister Abdullah Gul told reporters before departing for a trip to the United States.

Representatives of the Muslim community in Canada also praised the Pope for his apology on Sunday.

"We commend him for offering the apology," said Mohamed Elmasry, president of the Canadian Islamic Council. "I think he is setting an example to youth all over the world, not only to Catholics, but youths of other faiths that even the Pope can make a mistake, and if you do make a mistake you can offer regret, or retraction or apology."

"Right now is a time for healing," he added, saying there was a need for more understanding between Roman Catholics and Muslims.

With files from the Associated Press