Washington Nationals catcher Wilson Ramos was abducted by gunmen from his home Wednesday night. There's still no sign of Ramos.
The 24-year-old was taken away in an SUV by four armed men.
Ramos was in his home country of Venezuela playing winter ball.
A person close to his family said there has been no contact between the kidnappers and the Ramos family.
Major League Baseball and the Nationals issued a joint statement that the league's Department of Investigations was working with authorities.
"Our foremost concern is with Wilson Ramos and his family and our thoughts are with them at this time," the statement said, adding there would be no further comment.
There's been a sharp rise in kidnappings for ransom in Venezuela. Police said that 618 kidnappings were reported in 2009, and the numbers have grown rapidly in recent years.
Security experts said the real number of kidnappings today is much higher because many cases aren't reported to authorities.
The Associated Press contributed to this report.