WASHINGTON — Patrolling federal lands is becoming more and more dangerous, a group tracking attacks on the officers said Wednesday, citing two park rangers killed in the line of duty in 2002 and an overall increase in threats and violence.

A list of incidents last year includes a park ranger killed along the Mexican border, officers who were shot at by a marijuana farmer, a run-in with chainsaw-wielding tree poacher, and a slew of threats and intimidation.

‘‘These aren't just low-level arguments that escalated. These are people who are willing to enact pretty hard-core violence,'' said Eric Wingerter, national field director for the group Public Employees for Environmental Responsibility.

The statistics and anecdotal evidence compiled by the group show an increase in acts of violence and intimidation in three federal land agencies — the Forest Service, Fish and Wildlife Service and Bureau of Land Management.

In the national parks, attacks against rangers declined slightly from the 2001 levels, although PEER believes that may reflect inadequate reporting.

An accurate comparison is impossible, the group concedes, because the federal agencies have no uniform reporting system and the Justice Department, which is supposed to track the figures, does not.

As a result, PEER had to file open records requests with each agency, and in some cases with each regional office, to obtain the information.

The lack of uniform reporting was among the criticisms leveled in a report last year by Interior Department Inspector General Earl Devaney. The report said drastic changes were needed in the department's law enforcement operation, and Devaney told Congress in January that the department was not moving with an appropriate sense of urgency.

Interior Department spokesman Mark Pfeifle said the department is increasing its emphasis on law enforcement, providing intensive training on how to deal with dangerous situations and putting more officers in its most dangerous areas.

‘‘We've doubled the number of officers on the southern border.'' Pfeifle said.

Randall Kendrick, executive director of the U.S. Park Ranger Lodge of the Fraternal Order of Police, which represents park rangers, said rangers are still being sent into the field with inadequate equipment or backup, but things are getting better.

In 2002, park ranger Kris Eggle was shot to death at Organ Pipe Cactus National Monument along the Mexican border while trying to help apprehend a pair of murder suspects who had fled across the border.

A day later, U.S. Park Police officer Hakim Farthing, was killed by a drunken driver in Baltimore.

-Washington Parkway.