Congressional lawmakers are throwing up a web of challenges to the use of domestic drones, as federal and local officials start to pave the way for the surveillance aircraft to buzz freely inside U.S. airspace.

Sen. Rand Paul, R-Ky., is the latest to propose legislation cracking down on drones in the United States. The senator introduced a bill Tuesday that would prohibit governments from using drones without a warrant.

"Like other tools used to collect information in law enforcement, in order to use drones a warrant needs to be issued. Americans going about their everyday lives should not be treated like criminals or terrorists and have their rights infringed upon by military tactics," Paul said in a statement.

The bill follows a similar proposal earlier this month on the House side from Rep. Austin Scott, R-Ga. That bill is now before the House Judiciary Committee.

Plus Sen. Mike Johanns, R-Neb., just submitted an amendment to another bill to ban the Environmental Protection Agency from using drones for aerial surveillance -- a practice the EPA has defended as a cost-efficient way to monitor farmers' and ranchers' compliance with environmental regulation.

The flurry of anti-drone proposals comes as governments move to make the machines -- the armed versions of which are best known for their role in taking out militants inside Pakistan, Yemen and elsewhere -- more commonplace in the United States.

Last month, the Federal Aviation Administration outlined new rules for authorizing drones at potentially dozens of sites across the country. Local law enforcement agencies hope to use the drones more frequently for surveillance purposes.

The U.S. military is also planning to bring more drones from overseas into the United States, in part for training purposes. One Air Force official told Salon that the drones could be "integrated" into U.S. airspace, saying they fly "just like a Cessna or a 737" and arguing that privacy legislation may not be necessary.

The drones, though, are already here to some extent. The nonprofit group Public Intelligence released a map this week that identified more than 60 bases in the United States where drone "activities" have been recorded.

The bills by Paul and Scott carve out exceptions. Though the bill requires drone operators to obtain a warrant, it includes exemptions for drones that are patrolling the nation's borders, or being used to respond to a life-or-death situation including the possibility of terror attack.