Interval Censored Data and Parametric Survival Models in R Using survreg function

I wish to fit parametric survival models for interval censored data. However, I run into trouble while using the survreg function.
I used survival object of the form Surv(Start, Stop, Event) and I get a warning message indicating "invalid survival type". Is it not
possible to fit such parametric survival models using the survreg function? If so, is there any package in R which enables fitting of such
models?

Best Regards,
Pryseley