Montgomery County Police released the audio from the 911 call reporting Danielle and Alexander Meitiv's children, 10 and 6, walking down the street unaccompanied. Montgomery County police said that a call came in to check on the children’s welfare shortly before 5 p.m. (Montgomery County Police)

A D.C-based law firm will file suit and pursue “all legal remedies” to protect the rights of the Maryland parents whose two young children were taken into custody for more than five hours Sunday after someone reported them as they made their way home unsupervised from a Silver Spring park, the firm said Tuesday.

Danielle and Alexander Meitiv were “rightfully outraged by the irresponsible actions” of Maryland Child Protective Services and Montgomery County police, said attorney Matthew Dowd, of the firm Wiley Rein, in a written statement.

“We must ask ourselves how we reached the point where a parent’s biggest fear is that government officials will literally seize our children off the streets as they walk in our neighborhoods,” he said.

Dowd was not immediately available for comment Tuesday, but said through a spokeswoman that the firm would file the legal action “soon.” He declined to say through the spokeswoman who the suit is being filed against. The firm is representing the family pro bono.

Danielle and Alexander Meitiv let their children, 10 and six, walk home alone from a park a mile away from their house. Now, Montgomery County is investigating the couple for child neglect. (Jorge Ribas/The Washington Post)

The Meitivs’ children were picked up by police as they walked home from Ellsworth Park at 5 p.m. Sunday. Their parents had expected them home by 6 p.m. and Danielle Meitiv said they frantically searched for Rafi, 10, and Dvora, 6, before being notified at 8 p.m. that CPS had the children.

The statement issued Tuesday said the children were three blocks from their house when they were stopped by officers in three squad cars and “subjected to a terrifying detainment that no child should have to experience.”

“Shockingly, the Meitiv children experienced this maltreatment at the hands of the very government officials who are entrusted to uphold the law and ensure that children in need are taken care of,” it said.

The Meitivs are believers in a “free range” style of parenting, which holds that children learn to be self-reliant by progressively testing limits and being allowed to roam the world without hovering adults.

The statement alleged that the pair were detained in a police car for almost three hours, kept from their parents for over six hours without access to food, and “not returned to the parents until almost midnight on the night before school.”

In an interview with The Washington Post, Danielle Meitiv said that her son told her the children were misled into believing police would take them home. Police had all the Meitivs’ contact information and did not call the parents, or allow the children to call their parents, the statement alleges.

Danielle Meitiv said that she and her husband arrived at a CPS crisis center at 8:30 p.m. and were allowed to see their children at 10:30 p.m. and take them home. Meitiv said the family had to sign papers saying the children would not be unattended while CPS followed up on the case.

Legal age restrictions for children left at home alone. Some are guidelines and some states may have more definitive laws than others.

Montgomery County police said Monday that a call came in to check on the children’s welfare shortly before 5 p.m. and that an officer found the children in a parking garage. Police said an officer saw a “homeless subject” who was “eyeing the children.”

Police said the officer notified CPS, as is required in circumstances involving possible child abuse or neglect. After a series of calls, police say the children were left at CPS at 7:43 p.m. Police said the officer followed the direction of CPS in the matter.

CPS officials would not answer direct questions Monday, but issued a statement saying that “protecting children is the agency’s number one priority. We are required to follow up on all calls to Child Protective Services and will continue to work in the best interest of all children.”

The Sunday episode followed an earlier incident when the Meitiv children were picked up by police as they walked home from a different Silver Spring park, about a mile from their home. In both instances, callers reported the children to police.

In the earlier case, the parents were held responsible for “unsubstantiated neglect” and informed that CPS would keep a file on the family for at least five years.