Philadelphia ? For the third time since the 1970s, members of MOVE the radical group whose 1985 clash with police left 11 people dead and 61 homes burned to the ground began boarding up their windows last week for another possible showdown.

This time, the source of tension is a child-custody dispute. Police and city officials have tried to defuse tensions, giving assurances that they do not plan to intervene in the custody case.

An unidentified MOVE member walks with a child past a fortified window in their compound in Philadelphia. Members of MOVE, the radical group whose 1985 battle with police left 11 people dead, began boarding up their windows last week for another possible showdown. This time, the source of tension is a child-custody dispute involving one of its members.

But the buildup and the prospect of another armed clash have baffled police, who thought that MOVE’s members had mellowed and even gone middle-class.

Police Capt. Bill Fisher, head of the civil affairs division, said he had been to the house “maybe 50 times” to visit with MOVE leaders in recent years and thought he had established a good relationship.

“During the period I have dealt with them, I have never seen any violence or vandalism. I’ve never seen a knife. I’ve never seen a gun. I was totally shocked when they went to this mode,” Fisher said. “In the five years I’ve been here, it’s a kinder, gentler MOVE, but here I am standing outside a boarded-up house.”

At issue is a judge’s order that MOVE member Alberta Africa turn over 6-year-old son Zachary for weekend visits with his father something she has refused to do. While Zachary and his mother have spent time at the MOVE headquarters in Philadelphia, they live in Cherry Hill, N.J.

Nevertheless, MOVE spokeswoman Ramona Africa, who was burned in the 1985 fire and went to prison for seven years, said MOVE members fear police will use the custody dispute “as an excuse to exterminate MOVE.” She said they had boarded up the home in self-defense.

MOVE got its start in the early 1970s. The mostly black group shunned modern conveniences, preached equal rights for animals and rejected government authority. Members dropped their surnames and took the last name Africa. The name MOVE does not stand for anything in particular.

Years of tension between MOVE, neighbors and city inspectors exploded in 1978, when police stormed their fortified West Philadelphia commune and were met with gunfire. One policeman was killed. Nine MOVE members went to prison for murder.

By 1981, MOVE was back at a new headquarters in a West Philadelphia rowhouse. Neighbors complained the group was allowing garbage to pile up and shouting profanities through a loudspeaker late into the night.

On May 13, 1985, police moved in to arrest several MOVE members. After a daylong siege, the city dropped a bomb from a helicopter to try to dislodge a rooftop bunker, touching off a fire that destroyed an entire block and killed six adult MOVE members and five children.