The federal government is not fully prepared to handle a nuclear terrorist attack or other sort of large-scale natural catastrophe, and in some cases is years away from ensuring adequate emergency shelter and medical treatment for U.S. citizens, congressional investigators have found.

The Federal Emergency Management Agency has not always kept track of disaster efforts by agencies due to lack of effective coordination, which affected the preparedness of states even after Superstorm Sandy devastated the northeast in 2012, according to the congressional audit, reported by the nonpartisan Government Accountability Office and obtained by the Associated Press.

"FEMA is not aware of the full range of information," the investigational report states, which partly relies on internal documents from the Homeland Security Department.

Additionally, the report also accused the Energy Department of not effectively coordinating with state agencies and the private sector during Superstorm Sandy, which was blamed for at least 182 deaths and $65 billion in damage.

In concern to natural catastrophes, the report said FEMA should take a bigger responsibility in leading a coordinated response, setting clear minimum standards for agencies and collecting regular status reports, according to Fox News.

In order to determine whether people have been exposed to unsafe levels of radiation after an attack, it would take one to five years to develop a strategy and five to 10 years to plan for a full medical response, the GAO said. To ensure that agencies fulfill their goals, FEMA needs to set deadlines since the interagency group is responsible for creating a disaster response plan, investigators said.

"This report makes clear that there are some areas of our country's preparedness that need strengthening up," said Sen. Bob Casey, D-Pa., who co-chairs the Senate Caucus on Weapons of Mass Destruction Terrorism.

Although FEMA would be able to work towards fulfilling the GAO recommendations by June, it did not have the legal authority to compel other agencies to take action, Jim Crumpacker of Homeland Security said

"FEMA will continue to coordinate and collaborate with other federal departments and agencies," Crumpacker wrote in a response included in the GAO report.

Meanwhile, 39 of 102 corrective actions identified by federal agencies after Superstorm Sandy still need to be done, which include improving emergency coordination with states, ensuring adequate transportation of injured victims, and boosting training in the use of electronic medical records and other care, according to the report.