Staff accused of eating pizzas in front of inmates, amid calls for their release from for-profit detention centres.

A series of mass hunger strikes have rocked for-profit detention centres across the US, as rights groups call for asylum seekers to be released while their cases are pending.

Hundreds of immigrants, including asylum seekers, have participated in the hunger strikes in California, Texas and Louisiana.

At least 26 asylum seekers are on hunger strike in the Adelanto facility, a for-profit detention centre in southern California.

They are all that remain of an original 90 hunger strikers who launched the collective fast on November 4.

According to CIVIC, a US-based advocacy group that campaigns for immigrant detainee rights, the US Immigration and Customs Enforcement (ICE) has taken punitive measures in a bid to break the hunger strike.

“There has been a lot of intimidation and threats against the hunger strikers to reduce [their] numbers,” Victoria Mena, a monitor at CIVIC, told Al Jazeera, adding that guards have “threatened expedited deportation” in some cases.

In some cases, guards have ordered pizza and eaten it in front of their cells “to tempt them into eating”, she said.

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Mostly fleeing from political persecution in countries in the Middle East, Africa and Southeast Asia, the hunger strikers released a list of demands on Wednesday. “We will not eat until we see our freedom,” the letter reads.

After turning themselves in at the US border and requesting asylum, the men were brought to the detention centre and issued bails ranging between $24,000 and $54,000, according to Mena.

“We can’t buy our freedom with a bond of $50,000 or $45,000,” the letter continues, adding that they fled their countries under the belief that the US “fights [for] justice for all”.

The strike was held at the same time that another 300 other hunger-strikers – immigrants who were not seeking asylum – refused food for more than a week in the Adelanto centre. They were protesting against harsh conditions, including poor food, limited access to healthcare and harassment by guards.

“This shows how wrong and how devastating this immigration system is,” Mena said. “People are willing to risk their lives to show exactly what is happening in these facilities.”

Like many of the more than 250 immigration detention centres in the country, Adelanto is administered by Geo Group, a Florida-based private contractor, as part of an agreement with ICE.

The US Congress has set a national quota mandating that ICE hold at least 34,000 immigrants in detention centres each day.

“Profit is being placed over people’s lives,” Mena said. “The US tells other countries how to handle refugees, but we are putting refugees in jail for undisclosed amounts of time while companies make a profit.”

Strikes spreading

Elsewhere, in the T Don Hutto detention centre in southern Texas, a mass hunger strike that started more than two weeks ago peaked with an estimated 500 women, mostly asylum seekers, refusing to eat.

The women are now holding rolling hunger strikes in which 40 to 50 residents of each section of the detention centre take turns refusing food.

Most of the hunger-striking detainees are from El Salvador, Guatemala and Honduras, where female murder rates rank first, second, and seventh, respectively, in the world, according to UN figures.

T Don Hutto’s spokesperson has denied that a hunger strike is taking place.

Meanwhile, ICE released a statement saying that it “takes the health, safety and welfare of those in our care very seriously, and we continue to monitor the situation”.

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However, according to Cristina Parker, of Grassroots Leadership, an Austin-based group that campaigns against for-profit detention centres, ICE has been interrogating and monitoring hunger strikers.

“They’re doing this even though they deny the hunger strike is taking place,” she told Al Jazeera.

At least six hunger strikers have been transferred from T Don Hutto since the strike started.

“The women feel like the moves to other detention centres were definitely punitive. They were moved in the middle of the night without prior notification,” said Parker.

In mid-October, 54 Southeast Asian asylum seekers held a week-long hunger strike in a detention centre in El Paso, Texas.

In Lasalle detention centre in Louisiana, 14 detainees held a two-week hunger strike in solidarity with the women in T Don Hutto.

Texans United For Families, a coalition of immigrant rights groups, has released audio recordings of phone conversations with the women still on hunger strike in T Don Hutto.

“I cannot continue here because I spent two days in the ice box for punishment,” one of the women says, referring to solitary confinement.

Follow Patrick Strickland on Twitter: @P_Strickland_