New figures reveal a sharp increase in the number of searches of Americans' calls and messages by the intelligence community during the Trump administration's first year in office.

The figures, published Friday by the Office of the Director of National Intelligence (ODNI), show a rise in targeted surveillance and searches of people's data. It's the latest annual report from the government's chief spy, which has faced calls to be more transparent in the wake of the Edward Snowden disclosures into its surveillance programs.

According to the figures, 7,512 searches of Americans' calls and messages without a warrant, up by 42 percent on the year prior.

The government gets these search powers under the controversial section 702 authority, which allows the National Security Agency (NSA) to gather intelligence on foreigners overseas by collecting data from choke points where fiber optic cables owned by telecom giants enter the US. The powers also authorize the collection of data from internet giants and tech companies.

But data collected under section 702 is near indiscriminate, and it also sweeps up large amounts of data on Americans, who are constitutionally protected from warrantless surveillance.

The actual number of searches on Americans is likely significantly higher, because the reported figures don't account for searches by other civilian agencies, like the FBI or the Drug Enforcement Administration -- which also don't require a warrant to search the database.

"We're almost certainly talking about tens of thousands of Americans being queried by FBI but have no clear info on that or the number of Americans whose data is collected," said Jake Laperruque, senior counsel at the Project On Government Oversight.

Congress has long asked the government to reveal how many Americans have their data inadvertently collected by the NSA. Both the Obama and Trump administrations refused to disclose how many Americans are caught up in the dragnet.

"Overall the numbers show that the scale of warrantless surveillance is growing at a significant rate, but ODNI still won't tell Americans how much it affects them," said Laperruque.

It's not the only figure in the report to see a massive increase.

The NSA targeted 129,080 foreign individuals or groups, representing a rise of 20 percent in the number of targets on the year earlier.

Patrick Toomey, staff attorney at the ACLU's National Security Project, tweeted that the figure was the "biggest jump on record."

The report also shows a massive spike in the number of collected phone records last year. The details of who calls who and when, collected under the NSA's phone metadata collection programs, was later curtailed when the Freedom Act was ratified in 2015.

Last year, a staggering 534 million call detail records were collected, up from 151 million -- more than a three-fold increase on the year earlier. The figures don't represent the number of Americans whose phone records were collected, and likely includes duplicates, the report said.

The number of orders to collect phone records, however, remained the same on the previous year.

Robyn Greene, policy counsel and government affairs lead at New America's Open Technology Institute, said the intelligence community may have changed interpretations of their legal authorities.

"The report raises some serious questions if the intelligence community, and the courts may be interpreting their authorities in an overbroad manner to permit too much collection," said Greene.

"It's hard to imagine how you get the same number of targets yet over three-times as many records collected unless you've reinterpreted what constitutes a call detail record," Greene added.

The report also showed a similar pattern with national security letters, a subpoena-like power that can compel tech and phone companies to turn over data on grounds of national security.

Although the number of letters increased marginally by 5 percent to 12,762 last year, the number of requests for information more than tripled, indicating that the FBI sought more data per letter than in previous years.

These letters are particularly controversial because they require no court approval and almost always include a gag order, which prevents the subject of the letter from being informed.

In recent years, several companies including Apple, Facebook, Microsoft, Twitter, and Yahoo have fought to have details of the secretive letters publicly revealed.

In 2008, a US court found the National Security Letter statute, amended by the Patriot Act in 2001, was unconstitutional. A separate case in 2013 found that the gag order provision was found to be in breach of the First Amendment, though the government appealed the ruling.

Timothy Barrett, a spokesperson for the ODNI, told ZDNet that the government has not altered its authority to obtain call records and that the number fluctuates from year to year.