Greece recovered the bodies of four dead migrants and rescued 27 others after their boat sank off the island of Kos in the southeastern Aegean Sea, the Greek coastguard said late on Tuesday.
Three coastguard ships and a commercial vessel were searching for more people in the area, it added.
In a separate incident early on Wednesday, a cargo ship rescued 96 migrants after their boat sank off the tiny island of Gavdos, near the island of Crete in the Mediterranean Sea, the coastguard said.
It said one of its vessels with four other ships and a helicopter were searching for any missing people amid moderate winds.
Greece was at the frontline of a migrant crisis in 2015-2016 when more than a million people, mostly Syrian refugees, crossed from Turkey to the country by sea, mostly on inflatable dinghies.
The number of arrivals fell before resurging last year as many migrants attempted the new southern route through Gavdos.
South Korea and the United States will cut short annual joint military drills to five days from 11 and scale back some field training, the allies said on Wednesday, after President Donald Trump ordered a substantial reduction in US participation.
At least 100 people were killed when a low-tech artisanal gold mine collapsed in the Central African Republic on Tuesday, a senior official at a local mining association said.
An Israeli airstrike killed nine Palestinians at a police station in Gaza on Wednesday, medics said, two days after US envoy Jared Kushner ended a trip to the region that failed to push forward Donald Trump's plan to end the war in the enclave.
Thai schools conducted active shooter drills on Wednesday, as authorities moved to strengthen security measures two weeks after a 14-year-old opened fire at a school and killed at least eight people.