The PATH subway tunnels in New York are getting an overcoat to protect them from terrorism.

Port Authority officials are lowering massive "blankets" over the near-exposed PATH subway tubes beneath the Hudson River, said a NY Post report. The PATH is especially vulnerable to bombs because the century-old tunnels are not dug into bedrock. Instead, they're inserted below a layer of thick silt and mud.

According to the report, the pads would reduce the amount of water that would flow into the tunnels in case of an explosion, and would also help them resist the blast by exerting pressure on the tube.

All four tubes below the Hudson -- two going to the World Trade Center, two going to the West Village -- are expected to get the treatment, the report said.

The work has progressed from the Jersey City shoreline -- not far from the PATH hub at Exchange Place -- toward the World Trade Center.

While the measures may not prevent terrorism, the report said they could reduce the level of damage to the system from an attack and ensure the safety of thousands of passengers.