SACRAMENTO (AP) Construction was halted at the city’s most ambitious development project after contractors filed liens against the developer for what they said are unpaid bills totaling $7.3 million.

Cost overruns have forced developer John Saca to seek additional financing for the two 53-story condominium and hotel towers planned just blocks from the state Capitol, said his spokesman, Eric Rasmusson.

“John has been working every single day on this project for over three years and would not continue to do so if he didn’t think there was sufficient reason to do so,” Rasmusson said.

The 600-ft. (183 m) towers would be the tallest residential structures on the West Coast, according to Saca.

Saca is seeking further investments from the California Public Employees’ Retirement System, which already agreed to invest $100 million in the project. Its advisers are weighing whether to contribute more and how to ensure their investment is protected, said Ted Eliopoulos, the fund’s new head of real estate investment.

The Sacramento City Council approved an $11 million subsidy for the hotel portion of the towers in October, after Saca said construction costs on the $500 million project had skyrocketed by more than $100 million.

The city is also seeking to help Saca secure additional funding from CalPERS.

“This is a very important project to the city of Sacramento, particularly since a building has been torn down and there are piles in the ground,” said John Dangberg, the city’s assistant city manager for economic development. “We’re not interested in having a hole at the gateway to the Capitol Mall.”