UPDATE 1-U.S. Lawmaker Says Paris Attacks Highlight Encryption Concerns

(Adds more quotes, background)

By Patricia Zengerle and Dustin Volz

WASHINGTON, Nov 17 (Reuters) - The chairman of the U.S. Senate Intelligence Committee said on Tuesday it was likely that end-to-end encryption was used by individuals in Belgium, France and Syria who were involved in the Paris attacks last week.

"We can't tell you today specifically that they were using a specific encrypted platform. We think that's a likely communication tool because we didn't pick up any direct communication (before the attacks)," Republican Senator Richard Burr told reporters.

Hawkish lawmakers and several intelligence officials seized on the Paris attacks this weekend to argue that they illustrate the dangers of increasing encryption.

"I think it's safe to say that there are 30 end-to-end encrypted software packages that you can download for free. And, given the fact that between iTunes and PlayStation, the number of apps that are added on a weekly and monthly, yearly basis, and I think we anticipate that everything from this point forward will have an encrypted communications to it," he said.

"Now's the time for us to act," Burr said.

He said the committee was far from developing legislation to address the issue, and that it was trying determine the options that are available and then would decide the best course, short, medium and long-term.

Intelligence agencies have long warned that the rise of encrypted email, chat and phone platforms has made it more difficult to track suspicious activity. Senior Obama administration officials have pushed to allow for so-called "backdoors" that would give the intelligence community a way to access encrypted communications.

Privacy advocates, technology companies and security researchers generally oppose such vulnerabilities, warning that any weakness built in for law enforcement or national security officials could also expose information to foreign nation states and malicious hackers.

After a classified briefing on the Paris attacks, Burr told reporters that U.S. investigators were in Paris but "not active in the investigation." He said France has not asked for assistance from Federal Bureau of Investigation explosives experts. (Reporting by Patricia Zengerle and Dustin Volz; Editing by Toni Reinhold)