Ahead of SpaceX’s experimental rocket launch Monday (Aug. 26), police warned nearby residents to leave their homes around launch time because the windows could shatter, according to the Brownsville Herald.

Those residents live in tiny Boca Chica Village, Texas, which sits less than 2 miles (3 km) from a SpaceX-operated launch site near the US-Mexico border along the Gulf Coast. SpaceX’s test of the so-called “Starhopper”—a prototype of a reusable shuttle meant for human transit—may well create an “overpressure event” capable of breaking glass in buildings nearby. The police-delivered warnings advise residents to, at a minimum, exit their homes when they hear police sirens around the 4pm launch window.

Comments posted under the Brownsville Herald article include, “Doesn’t sound good to me that they have to evacuate their homes all because Space X is testing” and “I think spacex should be prepared to pay for the window replacements.”

In addition to the alerts, local law enforcement announced planned road closures on the only highway available to nearby residents, and to an area beach.

The warning also reads in part, “it is recommended that you consider temporarily vacating yourself, other occupants, and pets, from the area during the Space Flight Activities.”

In July, SpaceX launched the Starhopper for the first time, from the same site. Flaming debris from that operation led to brush fires that spread across about 100 acres.