As many as 112 elderly people in Washington and neighboring Maryland suburbs were mugged or robbed in the last year by a gang of youths who trailed victims from shopping centers to their homes before assaulting them, Montgomery County police said yesterday.

Police said the muggers, who apparently operated in teams, are responsible for several severe injuries, including one attack on a rabbi who was beaten while walking to Sabbath services in Silver Spring and another assault on a Kensington woman who suffered a fractured skull.

The gang used several vehicles to help obscure their stalking of potential victims and to make police surveillance difficult, police said.

Two young Washington men, who police allege are members of the gang, have been arrested. They were charged with two robberies and are being investigated in connection with the others, police said.

According to police, as many as six other persons are believed to be gang members and are currently being sought in connection with the beatings and robberies. Prince George's County and District police are involved in the investigation, the police spokesman said yesterday.

According to Cpl. William Ingles of the Montgomery County police robbery squad, the gang operated in upper Northwest Washington, the southern portion of Montgomery County and the Langley Park Adelphi area of Prince George's County.

Ingles said the gang apparently began operating last winter. Although police were aware of the increase in the type of crime and had set up surveillance teams, he said they didn't perceive a pattern to the robberies in the three jurisdictions until late last summer.

"There'd be two to three (robberies in Montgomery County) a night where the modus operandi (robbery method) was the same," he said. "Then we noticed that the same night there were six or seven incidents with the same pattern throughout the area."

The gang apparently favored staking out shopping centers where members waited for an elderly person who appeared to be a likely candidate for robbery he said. The gang members would then trail the victim to his or her home or apartment he said.

The victim was assaulted or robbed as he or she stepped from a car or entered the home, he said.

Ingles said despite surveillance efforts police never witnessed a robbery. However, he said, an incident in December led to arrest of the two men currently charged and the discovery of identities of six other individuals.

According to police, Steven G. Hill, 20, of 7532 9th NW in Washington has been charged with two counts of robbery, and 18-year-old James L. Perry Jr. of the same address with one count of armed robbery. Police said both men are "definitely" members of the gang.

A large number of elderly people live in the roughly triangular area where robberies occurred, police officials and others familiar with the problems of the elderly said.

Cpl. Cliff Melton of the Montgomery County police said about 17,000 of the county's 70,000 residents over 60 live in the Silver Spring area close to both the District and Prince George's border. Estimates were unavailable for the number of elderly people living in the District and Prince George's sections of the area.

Local police officials yesterday said that while elderly citizens as a group are far less vulnerable to crime than those in the 25 to 29 age group, (if only because the elderly tend to go out less) they're particularly susceptible to being either duped in a confidence swindle or seriously injured in an attack because of age and frailty.

Police said Hill, who was arrested Jan. 27, has been released on bond. Perry, arrested Feb. 1, is being held in lieu of bond at the Montgomery County detention center, police said.