Suffolk County officials say they are considering legal action to block the Heartland Town Square project that is planned for the Pilgrim State Psychiatric Center property.

The plan calls for thousands of apartments, plus retail and office space. The Islip Town Board gave the project the green light last week, but the county's Planning Commission is now reviewing its legal options due to several sticking points.

County officials say Islip leaders voted to override certain conditions from the commission for the massive redevelopment project, including clauses about an apprenticeship program, traffic and the number of affordable housing units.

The original plan included 9,000 apartments, but the Islip Town board voted unanimously to approve just the first phase of the project, which would bring roughly 3,500 apartments, plus retail and office space.

The county Planning Commission says the other three towns that border the project -- Huntington, Babylon and Smithtown -- must also be on board with the project's terms. If even one town does not give the OK, the commission says it can vote to overturn Islip's rezoning.

The project's developer tells News 12 he doesn't believe the planning commission has any basis to overturn Islip's decision.

News 12 reached out to town officials, who said they cannot comment.

Some residents who spoke with News 12 said they expect the project to bring jobs and needed housing to the area, but concerns were also expressed about the potential for increased traffic.