The ACLU is challenging Puerto Rico’s strict curfew, implemented to combat the spread of coronavirus, by seeking a legal injunction.

The ACLU argues the restrictions are unconstitutional in a lawsuit. The governor responded by imposing tighter restrictions.

The curfew was implemented on March 15 and has closed all non-essential business and mandated people stay home from 7 p.m. to 5 a.m. and remain there even outside those hours unless they have to buy food or medicine, go to the bank or have an emergency or health-related situation.

Violators face a $5,000 or a six-month jail term, and police have cited hundreds of people, according to the Associated Press.

The ACLU argues the curfew, which is currently in place until April 12, is unconstitutional because no martial law has been declared.

“There’s been no martial law declared, and there are no circumstances for it,” the ACLU said. “As such, emergency states cannot be used to suspend fundamental rights.”

The lawsuit names three Puerto Ricans who say the exemptions to the ban are confusing. They worry they may be arrested as they leave their homes to care for elderly mothers and relatives that need insulin injections.

On Sunday, Gov. Wanda Vázquez imposed more regulations. She said nearly all businesses including supermarkets and banks must close on the three days from Good Friday through Easter Sunday, with only pharmacies and gas stations allowed to operate. She said people will be allowed outside during that period only if they are seeking medical help or an essential service.

Gov. Vázquez ordered that until further notice, businesses prohibit entry to anyone not wearing some kind of face mask. She said scarves wrapped around the face would be acceptable.

It is the first time the ACLU has filed a lawsuit in a U.S. jurisdiction related to a coronavirus curfew. The ACLU filed the lawsuit in Puerto Rico’s Court of First Instance.

In a statement last month, the ACLU said it will keep monitoring the use of emergency powers during the COVID-19 pandemic.

“History teaches that our government is most prone to committing abuses in times of crisis, and we must ensure that broad presidential powers are not misused beyond legitimate needs,” it said.