hmas choules , which has previously been used to manus island detainees , has been employed by the navy to hand communist government in an operation which could cost $ 2.8 million of tax payers money .
it is understood that the asylum seekers were intercepted earlier in april , and are being returned through the port of vung tau , south of ho chi minh city .
the australian navy has allegedly returned up to 50 asylum seekers to vietnam in a secret operation .