HARTFORD: Muslims around the United States are facing a backlash following the deadly attacks in Paris, including vandalism to mosques and Islamic centres, hate-filled phone and online messages and threats of violence.

Advocacy leaders say they have come to expect some anti-Muslim sentiment following such attacks, but they now see a spike that seems notable, stirred by anti-Muslim sentiment in the media.

"The picture is getting increasingly bleak," said Ibrahim Hooper, a spokesman for the Washington, DC-based Council on American-Islamic Relations.

"There's been an accumulation of anti-Islamic rhetoric in our lives and that I think has trigged these overt acts of violence and vandalism."

He said the rise in the level of anti-Muslim sentiment is reflected by some GOP presidential candidates, governors and others speaking out in opposition to the US accepting more Syrian refugees.

Hooper said the council is seeing an increase in anti-Muslim incidents since Friday's attacks in Paris that killed 129 people and wounded more than 350.

At the University of Connecticut, authorities are investigating after the words "killed Paris" were discovered on Saturday written beneath an Egyptian student's name on his dorm room door.

Muslim leaders also have reported recent vandalism, threats and other hate crimes targeting mosques in Nebraska, Florida, Texas, Kentucky, Virginia, Tennessee, Ohio, New York and other states.

After the Paris attacks

The Omaha Islamic Centre in Nebraska reported that someone spray-painted a rough outline of the Eiffel Tower on an outside wall. The Council on American-Islamic Relations has called for the FBI and local police to investigate the incident as a possible hate crime, and they're doing just that, according to Nasir Husain, general secretary of the centre. Muslims in the central US city are afraid, he said.

In a suburb of Austin, Texas, leaders of the Islamic Centre of Pflugerville on Monday discovered faeces and torn pages of the Quran that had been thrown at the door of the mosque. Muslim leaders also encouraged authorities to investigate the act as a hate crime.

In a suburb of Houston, Texas, authorities on Tuesday arrested a man accused of threatening on social media to "shoot up a mosque." He was charged with making a terrorist threat, a felony.

Two Tampa Bay-area mosques in Florida received threatening phone messages on Friday night. FBI officials said the same person made the calls to the Islamic Society of St. Petersburg and the Islamic Society of Pinellas County. The person was identified and interviewed over the weekend, but investigators found no actual plans to carry out acts of violence, the FBI said. One of the calls threatened a firebombing.

Nihad Awad, national executive director of the Council on American-Islamic Relations, asked law enforcement officials to step up patrols at mosques and other Islamic institutions.