"We'll have to make difficult decisions on city spending, the likes of which have never before been needed," Philadelphia Mayor Jim Kenney said.

Manhattan office leasing experienced a healthy start to the year in January and February with a drop in availability and rise in rents. However, that was soon over when coronavirus arrived in March.

Thor Equities acquired the property last month to add to the firm's dedicated life sciences platform and meet the demand for laboratory and research and development space in the region.

In the near term, the development team will come up with a sustainable, viable program for Mare Island that is tailored to Vallejo's location, culture and character, and updated for the 21st Century.