As the number of immigrants entering the city rises, the police department is reaching out to newly arrived communities to reduce any friction in their relations with the police and gain their trust to reduce crime and prevent terrorist attacks, officials said.

Police Commissioner Raymond Kelly met yesterday with a group of African imams at the Masjid Aqsa in Harlem to address their concerns about the police. It was one of many meetings the commissioner has had with community leaders throughout the year, a spokesman said.

The group’s questions ranged from the more familiar issues — the racial tension since the Sean Bell shooting in November — to the lesser known: According to one imam, some recently arrived female immigrants women do not realize the consequences of a 911 call about domestic abuse.

“We are doing a great deal to educate our police officers about Islam. That’s part of our job,” he told the imams, who sat on the green, carpeted floor of the mosque. Mr. Kelly wore no shoes in accordance with the custom of entering a mosque.

Mr. Kelly’s latest community outreach event comes on the heels of his revival of a long-dormant unit in the Community Affairs Bureau, the New Immigrant Outreach Unit. The unit recently hired a former African community advocate, Sadique Wai, to reach out to members of the West African and other immigrant communities.

Mr. Wai will work alongside the department’s Muslim community coordinator, Erhan Yildrim, who has helped coordinate a pre-Ramadan security meeting with imams at police headquarters, as well as other events.

“I think that he realizes that in the way the city is now, with its diversity, we can’t police properly without developing relations with those communities,” the three-star chief in charge of the Community Affairs Bureau, Douglas Zeigler, said, adding that the Mexican and West African communities are growing at the fastest rate. Mosques are also being built in greater numbers, he said.

A sergeant in the Community Affairs Bureau, Lizbeth Villafane, leads the daily work of creating some of those relationships. She said her teams meet with politicians, religious leaders, and “anyone else who can give access to these communities.”

“Those leaders can open the door for us,” she said.

Since the terrorist attacks of September 11, 2001, Mr. Kelly has made it an official policy of the police department not to stop people in the city based on their race, a practice known as racial profiling. Still, some members of the Islamic community say Muslims feel targeted for questioning.

At a recent forum at the Islamic Cultural Center on 96th Street, many of the questions focused on the police department’s policies regarding racial profiling, the imam of the mosque, Omar Abu-Nabous, said.

The police department and the center have finalized an initiative through which regular patrol officers will visit the mosque to learn more about Islam. Precincts with high numbers of Muslims will hold similar visits at local mosques, Chief Zeigler said. Officers now watch a 30-minute film, “Streetwise,” which uses interviews with regular New Yorkers to explain Islam.

“It is important to understand the tenets of Islam, what it is really for,” Mr. Abu-Nabous said in an interview yesterday. He added that the cultural practices of Muslims, such as the way to proceed if a woman answers the door wearing a traditional headscarf and clothing, or what holidays are important to Muslims, are important to policing.

Another issue, Mr. Abu-Nabous said, is that police may treat a young person’s comments as more than youthful banter.

“Sometimes young people say some things which are sometimes stupid. Such a comment, supporting, for example, Hamas or Al-Jihad. They are taken for serious statements and are detained. It becomes a very big issue,” he said. “The police officers have to be better educated about these things.”

Community policing was an initiative originally touted when Mr. Kelly was first commissioner from 1992 to 1994 under Mayor Dinkins, but in the era after September 11 it taken on a new meaning and urgency. In recent counterterrorism briefings, Mr. Kelly has pointed to the growing number of homegrown terrorist attacks around the world as an indication that the NYPD may be the first line of defense against another attack on the city.

“We continue to ask all New Yorkers to look at events through the prism of 9/11,” he told the imams. “If you see or hear anything suspicious, anything that gives you pause, please notify the police department’s counterterrorism bureau.”