Upper Crust has abruptly closed most of its restaurants, let go about 140 employees, and will shut down permanently unless the gourmet pizza chain gets a cash infusion in the next few days, according to a trustee overseeing the Boston-based company.

At a hearing in US Bankruptcy Court Tuesday, the trustee, Mark G. DeGiacomo, said Upper Crust shut restaurants Monday night because it had just four days of supplies and only $14,000 in cash after company executives paid themselves a month’s salary in advance.