Simon Ostrovsky, the Vice News journalist who was reportedly seized by pro-Russian insurgents in eastern Ukraine earlier this week, has been released, according to his employer.

"VICE News is delighted to confirm that our colleague and friend Simon Ostrovsky has been safely released and is in good health," the website reports on Thursday.

"We would like to thank everyone for their support during this difficult time. Out of respect for Simon and his family's privacy, we have no further statement at this time," Vice News said.

As NPR reported on Wednesday, the American journalist was kidnapped by masked gunmen in the restive eastern Ukrainian city of Slovyansk.

Later, Stella Khorosheva, a spokeswoman for the kidnappers, said of their captive, "he's fine," but added that he was being held on suspicion of "bad activities." She did not elaborate.