It's not clear who was released or the reasoning behind it, according to reports.
No further details were given about the the release, according to the group that arranged for their mission trip to Haiti.
"We have learned that two of the hostages in Haiti were released," Ohio-based Christian Aid Ministries said in a statement Sunday.
The group was demanding $1 million ransom per person.
A man who identified himself as the leader of the gang posted a video on YouTube, saying that he was willing to kill hostages if the ransoms were not paid, The AP reported.