HAVERHILL — Two brothers were arrested yesterday on their way to court for their mother's hearing in connection with an incident that left a woman in critical condition at a Boston hospital.

Todd Muir, 23, and Justin Muir, 20, were charged with assault and battery with a dangerous weapon and assault with a dangerous weapon. They were ordered held on $7,500 cash bail by Judge Patricia Dowling.

The two were on their way to court for a dangerousness hearing for their mother, Ernestine "Tina" Muir, 40, of 6 Blaisdell St. Her dangerousness hearing, to determine if she should continue to be held without bail, was postponed to Friday because her lawyer was involved in a trial in Lawrence.

Police said Tara Hatfield, 33, of 402 River St., and her brother Shawn Hatfield, 32, of 1 Arlington Place, went to Ernestine Muir's home Saturday at 1:30 a.m. at the urging of Todd Muir after the Hatfields were drinking at a local bar.

Police said Ernestine Muir and Tara Hatfield had a confrontation that ended when Muir punched Hatfield in the face, causing her to fall to the ground where she suffered serious injuries to her head. Hatfield was rushed to Caritas Holy Family Hospital in Methuen before being taken by helicopter to Beth Israel Deaconess Medical Center in Boston, where doctors performed brain surgery.

Todd and Justin Muir are accused of chasing Shawn Hatfield from the scene and beating him with sticks.

During Justin's arraignment yesterday in Haverhill District Court, his lawyer, Edward English, asked for a lower bail, saying Justin has no court record and that he should be released.

Todd Muir's lawyer, David Stuehr, said his client had not been involved in any criminal incidents over the last several years and that his record includes six dismissals in Massachusetts.

The Muir brothers are scheduled to appear Aug. 25 in Haverhill District Court.

Tammy Muir, 38, sister-in-law to Ernestine Muir, said yesterday that Tara Hatfield was calling the Muirs' home prior to the incident and harassing Todd Muir and threatening to come to the house. Tammy Muir said Tara Hatfield came looking for trouble and intended to confront Todd Muir, whom she had dated briefly, about his new girlfriend.

"Tara was jealous," Tammy Muir said.

When the Hatfields arrived, Ernestine Muir tried to defuse the situation, Tammy Muir said.

"Tina (Ernestine) asked Tara to leave," Tammy Muir said, adding that the two women have known each other for seven years. "Tara shoved Tina, Tina shoved Tara, Tara swung at Tina and Tina responded."

Tammy Muir said the charges against Todd and Justin Muir are "bogus."

"There were no sticks and bats involved," she said.

A spokeswoman for the Essex County District Attorney's Office said Tara Hatfield is still at Beth Israel Hospital and her condition has been upgraded from critical to fair.