Ten Muslim civil rights groups have issued a joint letter denouncing the arrest of a Palestinian American community leader in Wisconsin, Salah Sarsour.

The president of the Islamic Society of Milwaukee and a vocal Palestinian advocate, Sarsour was reportedly pulled over by 10 federal agents from Immigration and Customs Enforcement (ICE) while driving on March 30.

The joint letter explains that Sarsour was transferred to a detention facility in Illinois, then to Indiana, leaving his family “scrambling to determine his whereabouts”.

A lawful permanent resident, he had lived in the US for 32 years, according to the letter, and his wife and children are all US citizens. Sarsour has been in immigration detention ever since his arrest.

“We must be clear that Salah is being targeted on the basis of his Palestinian and Muslim background,” the letter, issued Thursday, said.

It was co-signed by organisations including the Council on American-Islamic Relations (CAIR), the Muslim Legal Fund of America, and the US Council of Muslim Organizations.

The groups noted that, under President Donald Trump, a number of immigrant activists, scholars and foreign students had been targeted for deportation based on their pro-Palestinian solidarity.

“His detention reflects a troubling trend we’ve seen with Mahmoud Khalil, Leqaa Kordia, Mohsen Mahdawi and other voices critical of Israeli oppression,” the groups wrote.

“This administration is weaponizing the U.S. justice system to advance the interests of a foreign state, Israel, at a time when it is carrying out a genocide in Gaza.”

The groups have launched an online campaign for Sarsour’s legal defence. By Thursday afternoon, it had earned over $35,500 in donations.

While the Trump administration has yet to issue a statement about Sarsour’s arrest, it has taken a hardline approach to pro-Palestinian activism.

When running for re-election in 2024, Trump pledged to crack down on protesters denouncing human rights abuses during Israel’s genocidal war on Gaza.

According to statements obtained by the Washington Post in May 2024, Trump reportedly called the protest movement a “radical revolution” and said that, if he were elected, he planned “to set that movement back 25 or 30 years”.

Within months of taking office in January 2025, Trump proceeded to take action.

Starting in March 2025, his administration moved to strip hundreds of millions of dollars in federal funds from universities that saw protests unfold on their campuses, citing claims of anti-Semitism.

Federal agents also arrested legal permanent residents like Mahmoud Khalil, a Palestinian student leader, stripping him of his green card.

One scholar, Rumeysa Ozturk of Turkiye, saw her student visa revoked for co-signing a pro-Palestinian opinion piece in her school’s student newspaper.

The arrests and subsequent efforts to rapidly deport the activists and scholars have prompted widespread condemnation as a violation of the Constitution’s First Amendment right to free speech and protest.

Officials in Wisconsin have been among the leaders to denounce Sarsour’s arrest as the latest in a series of efforts to stifle free speech. Two local alderpersons, JoCasta Zamarripa and Alex Bower, called the situation a “nightmare”.

“This is an illegal detention of a longtime permanent U.S. resident, as Mr Sarsour is a Milwaukeean who is lawfully present in our community,” they wrote in a joint statement on Thursday.

“The unacceptable activities by ICE — and especially illegally detaining citizens without due process — must stop immediately. How dare federal ICE agents come into our community and unlawfully detain a grandfather, a faith leader, a Wisconsinite!”

State Senator Chris Larson, meanwhile, underscored that the federal government has yet to offer any reasons publicly for Sarsour’s arrest.

“We have already seen numerous Muslim activists unfairly and unlawfully targeted by the Trump Administration for their beliefs and their speech,” Larson wrote.

“These Unconstitutional assaults on our freedoms should alarm all of us. When any individual or group is targeted by the government for their speech, all of our freedoms are threatened.”