Prompted by deadly shootings in Dayton, Ohio, and El Paso, Texas, that left 29 people dead over a 13-hour period from Friday, the Foreign Ministry warned Japanese citizens in the United States to stay vigilant against such dangers.

"Heeding to the possibility that shooting incidents could happen anywhere in the U.S., which is a gun society, please continue to stay alert as a precautionary measure," the Consulate General of Japan in Detroit said in a statement on Sunday.

Two more shooting victims in El Paso later died of their injuries, raising the death toll in the two rampages to 31.