WASHINGTON — President Donald Trump on Thursday attempted to establish immigration as the defining issue of the midterm elections, calling Central American migrants heading to the southern border dangerous and announcing plans to prevent certain asylum seekers from entering the United States.

  • President plans to sign an executive order next week
  • Warns immigrants could be detained indefinitely
  • Critics say his immigration plan is illegal

“Migrants will have to present themselves lawfully at a port of entry,” Trump said in remarks at the White House. “Those who choose to break our laws and enter illegally will no longer be able to use meritless claims to gain entry into our country.”

Trump said he plans to sign an executive order next week that would deny asylum to those trying to enter the United States illegally. Immigration advocates contend this would violate current law, which allows anyone entering the country to apply for asylum no matter how they arrived.

Trump also reiterated unsubstantiated claims about the size and makeup of the migrant caravan making its way to the U.S.-Mexico border. He also warned that military personnel could open fire on the migrants if they engage in any violent acts toward the service members.

“Anybody throwing rocks...we will consider that a firearm, because there's not much difference when you get hit in the face with a rock,” Trump said.

Ahead of the midterm elections, Trump has been stoking fears about the migrant caravan, describing it as an “invasion” of criminals and gang members while offering little evidence to back up this allegation. The migrants say they are fleeing persecution, violence and poverty back home.

The size of the caravan has also been shrinking as it moves through Mexico.

Trump has been ramping up his rhetoric on immigration daily and accusing Democrats of wanting “open borders” and being soft on security. He intends to hammer this message on the campaign trail now through Tuesday’s elections, hosting at least eight rallies in 10 states.