Vanguard Group's global fixed income chief said Wednesday the company has tightened controls at some of its long-term bond funds to screen out "hot money" amid heavy cash outflows from rival Pacific Investment Management Co.

"We have a very robust process in place that screens out hot money," said Greg Davis, who oversees more than $800 billion in bond assets at Vanguard. "We've always had tightened controls. We've tightened them up some more."

Outflows from Pimco's Total Return Bond Fund have accelerated after star bond manager Bill Gross left the company last week to take a job at Janus Capital Group Inc, a much smaller company.

Davis said controls have been tightened, for example, at the $121 billion Vanguard Total Bond Market Fund because it is a prime substitute for the large Pimco fund formerly run by Gross.