T-Mobile prepaid brand MetroPCS hit back at AT&T’s Cricket on Monday with a new promotion after the latter attempted to woo Un-carrier customers with a $70 unlimited plan and $100 switcher credit.

For a limited time, MetroPCS said it is offering unlimited talk, text and data with 6 GB of 4G LTE data for $30 per line up to five lines. The 6GB of data is offered to customers who port at least one line to MetroPCS. Customers who don’t bring a new number with them will get 3 GB of high-speed data instead.

All customers taking advantage of the offer will get Music Unlimited, through which they can stream music data free from more than 40 streaming services, MetroPCS said. Customers will also be able to take advantage of the carrier’s Mobile Hotspot feature.

While the offer appears to be a response to Cricket’s recent promotion aimed at luring T-Mobile customers, MetroPCS targeted Sprint by name in its release.

The move comes as the prepaid competition between Sprint, T-Mobile and AT&T heats up. Verizon also has a prepaid brand, but CFO Fran Shammo admitted on the carrier’s recent earnings call that Verizon is “not very competitive” in the space.

According to a recent Consumer Intelligence Research Partners (CIRP) report, 42 percent of new T-Mobile customers during the quarter came from rival carriers, while the Un-carrier lost only 18 percent of its base to competitors. Sprint also gained a fair share – 30 percent – of its new customers from competitors during the quarter, but lost nearly as many (27 percent) to its rivals. The report did not distinguish between prepaid and postpaid customers.

In the first quarter, Verizon reported a loss of 177,000 prepaid customers. AT&T and T-Mobile will both release their first quarter results tomorrow. Sprint will report on Tuesday, May 3.