The FBI (search) and Department of Homeland Security (search) have issued a bulletin on school protection, recommending various measures that can be put into place to safeguard the nation's schools.

In the aftermath of the terrorist attack on a school in Beslan (search), Russia, last month that killed nearly 340 people, the two agencies issued a bulletin that said "there is no imminent threat to U.S. schools and the group that conducted the operation has never attacked or threatened to attack U.S. interests."

"However, the extensive media coverage and the high casualty rate generated by the incident ... warrant a summary of the lessons learned from that incident and protective measure guidance for helping to prevent and respond to a similar terrorist attack were it to occur in the United States."

In the bulletin sent out nationwide to law enforcement agencies and security personnel, the FBI and DHS suggest that schools consider secure locks for all external and internal doors and windows. They also suggest establishing a safe area within the facility for refuge during crises and having protective coating for windows on facilities that face traffic areas.

The agencies said that they are "currently unaware of any specific, credible information indicating a terrorist threat to public and private schools, universities or colleges in the U.S."

The agencies said that known incidents — most tied to hoaxes and unsubstantiated bomb threats — are tied to criminal and not terrorist activity. The FBI and DHS "continue to monitor and assess the validity of all information to identify any specific threats," according to the bulletin.

The FBI and DHS also suggest that schools review emergency crisis management plans and raise awareness among school workers and the community. They also suggest preparing the school staff to act in a crisis situation and to consider a closed-campus approach to population control.

"Law enforcement agencies, security personnel and educational administrators should be aware and remain alert to indicators of surveillance activities," the bulletin said.

Activities that may suggest terrorist surveillance of an educational facility include:

— Observation of security reaction drills or procedures.

— Increase in anonymous telephone or e-mail threats.

— Interest without reason in obtaining site plans for schools, bus routes, attendance lists and other information about a school, its employees or students.

— Discreet use of still cameras, video recorders or note-taking at non-tourist locations.

Lessons Learned

The FBI and DHS said in the bulletin that preliminary analysis of the tactics used by the terrorists against the Beslan school and the Russian authorities' response to the crisis has identified several things that law enforcement and school systems may want to consider when developing emergency response plans:

— It appears that about 30 terrorists used a stolen police or military truck for transportation to school grounds.

— Upon arriving at the school, the terrorists were stopped at a gate, but they opened fire, killing two and injuring two. They also killed six parents who rushed to help the guards.

— There are strong indications, according to the FBI and DHS, that the terrorists had pre-positioned a large cache of weapons within the school building prior to the attack. They may have used a group of ethnic Chechens involved in renovation work at schools in the area over the summer to hide the weapons or posed as construction workers themselves, according to the bulletin.

— The weapons may have been disguised as construction equipment at the school. There may have been false-fronted walls in the building.

"If these accounts are true, this would indicate that the attackers had been planning the attack for months, would have had detailed knowledge of the facility grounds and building interiors, and would have likely been conducting some type of pre-operational surveillance of building operations and staff," the bulletin states.

"The outcome of the attack on the school in Beslan affirms the importance of establishing a thorough response plan that outlines clear command and control responsibilities in the event of a potential terrorist or hostage situation," the bulletin continued. "In addition, the difficulty experienced by Russian authorities in maintaining an effective cordon during the Beslan incident highlights the importance of establishing and maintaining a secure perimeter."

FOX News' Anna Stolley contributed to this report.