U.S. Republican presidential candidates criticized Apple (AAPL) on Wednesday for opposing a government request for help hacking into an iPhone belonging to one of the San Bernardino attackers, calling the issue tough but important to boosting national security.

The company late on Tuesday said it was opposing a court order to help the Federal Bureau of Investigation break into an iPhone that belonged to the male shooter, Rizwan Farook, before the deadly Dec. 2 attacks in San Bernardino, California. Apple Chief Executive Officer Tim Cook said the demand threatened the security of Apple’s customers.

Donald Trump, a billionaire developer and a leading candidate for his party’s nomination to run for president on Nov. 8, said on Wednesday that unlocking the iPhone is “common sense.”

“I agree 100 percent with the courts—in that case we should open it up. I think … we have to open up, and we have to use our heads,” he said in an interview on Fox News.

U.S. Senator Marco Rubio of Florida, another candidate seeking the Republican party’s nomination ahead of the Nov. 8 election, called it a “tough issue” that would require government to work closely with the tech industry to find a solution.

At a campaign stop in Mount Pleasant, South Carolina, Rubio said he hoped Apple would voluntarily comply with the court order.

“Ultimately, I think being a good corporate citizen is important,” he said.