A Marine veteran from Illinois has been unlawfully detained in an Israeli prison, according to lawyers.

Jessica Clotfelter was one of the veterans aboard the Global Sumud Flotilla, a fleet of 42 boats heading to Gaza in an attempt to break the Israeli naval blockade and deliver life-saving medicine and food to Palestinians suffering from famine.

The Israeli Military intercepted the boats in international waters, detaining around 450 out of the 500 total people on the flotilla. 

As of Monday, 130 were still held captive, including Coltfelter. 

"It is completely lawful for the international community to try to break that blockade by bringing humanitarian aid, and that's exactly what these flotillas were doing. What is actually illegal is for any country to hinder humanitarian assistance," Farah Chalisa, an attorney representing Clotfelter, said. 

"They were also arrested in international waters. Holding their boats hostage, boarding their boats, and now holding Jessica and the other passengers hostage, that is all extremely illegal," she said.

Neither Chalisa nor Clotfelter's family has been able to make direct contact with her. 

For her brother, Trevor, and mother, Shelly, the unknown is the hardest part.

"It's the lack of information. Then your mind just is running, playing all the what-if scenarios while she's in detention," Trevor said.

" I 100 percent support her and her mission, because I know that's who she is," Shelly said. 

"As a mother, even though I worry, and I don't know what's going on with her, I know in my heart that she will be okay spiritually, because she is led by her faith," she said.

Clotfelter was once on the security detail for Marine Helicopter Squadron One, the helicopters responsible for transporting the U.S. president and vice president.  

CBS New's Chicago's Suzanne Le Mignot spoke with Clotfelter and Greg Stoker, the organizer of the U.S. veteran's delegation on board the flotilla, less than an hour before both were detained on October 1st. "I feel like we're as prepared as we will ever be," Clotfelter said.

After his release on Monday, Stoker shared several videos on social media about his experience.

"We were told there are no doctors for animals," Stoker said. 

"No showers, food scarcity, a lot of people are on hunger strike because they are withholding insulin from some of our detainees," he said. "There is no transparency, and none of us have seen lawyers."

Chaslisa stated that she was not allowed to make direct contact with Clotfelter, citing that the U.S. had not yet made contact with her or Jessica's attorney in Israel. "We both have signed authorization and power of attorney, which Jessica signed before she left for her mission," Chalisa said. 

On social media, Stoker credits his and another veteran's release in part to their respective senators making public statements, calling for their release last week. 

Clotfelter's family and legal team are calling on Illinois senators Dick Durbin and Tammy Duckworth to do the same. 

"We have asked for them to meet with Trevor and Shelly personally to talk about what they are doing to ensure that Jessica is returned to the U.S. as soon as possible," Chalisa said.