(Reuters) - A Wisconsin woman suspected of fatally shooting a pregnant woman who was just days away from giving birth was added to the Federal Bureau of Investigation's "Ten Most Wanted Fugitives" list, the agency said on Tuesday.

A reward of up to $100,000 is being offered for information leading to the arrest of Shanika Minor, 24, who is wanted for murder in the shooting of the 23-year-old expectant mother early on the morning of March 6 in Milwaukee, the FBI said.

It said the incident began with Minor confronting the woman, who was the neighbor of Minor's mother and identified by local police as Tamecca Perry, over playing loud music at night.

During the initial confrontation, Minor brandished a gun and fired a shot into the air before leaving in her car. Minor returned hours later and sparked another confrontation at the back door of the victim's home, the FBI said.

Minor's mother stepped between her daughter and the victim, pleading with her to stop, when Minor reached over the mother's shoulder and shot Perry in the chest, the FBI said.

Perry, who was a former high school classmate of Minor, retreated into her home, where she died in front of her two children, the FBI said. The agency said the unborn child also died before paramedics arrived.

Minor then fled and has not been seen since. The FBI said Minor had no known reliable employment and is likely being helped by friends.

"Our hope is that whoever is assisting her will find the potential reward more attractive than protecting a person wanted for first-degree murder," FBI Special Agent Chad Piontek said in a statement.

"This was a senseless crime," Piontek said. "And we believe Minor is capable of more violence."

Minor is the tenth woman to be placed on the Ten Most Wanted Fugitives list since its establishment in 1950, the FBI said.

(Reporting by Curtis Skinner in San Francisco; Editing by Dan Grebler)