North Korea has fired several short-range projectiles into the sea, South Korea’s defence ministry said, the BBC reports.
It comes hours after the UN Security Council unanimously voted to impose some of its strongest ever sanctions against North Korea.
A South Korean spokesman told the Yonhap news agency the projectiles were fired at about 10:00 local time (01:00 GMT) from Wonsan on the east coast.
He said they were still trying to determine exactly what was fired.
Yonhap quoted officials as saying all the objects fell into the sea.
The new UN measures are a response to North Korea’s recent nuclear test and satellite launch, both of which violated existing sanctions.
They will result in all cargo going to and from the country being inspected, while 16 new individuals and 12 organisations have been blacklisted.