(Reuters) - A coalition of 60 civil rights groups is calling on Google to disclose monthly data on the number of so-called "geofence" and "keyword" warrants the company receives.

In a Tuesday letter to Google Chief Executive Sundar Pichai, the Surveillance Technology Oversight Project, the Electronic Frontier Foundation, the Project on Government Oversight and other groups asked the company to provide more specific information about the non-traditional warrant requests, which they say "demand far more data than in the past."

Google did not immediately respond to a request for comment on the Tuesday letter.

Geofence warrants are a fairly new investigative method compelling the disclosure of anonymized records from devices that were in a certain area during a specific period of time. The warrants, also known as reverse location warrants, have started to face legal challenges under the 4th Amendment to the U.S. Constitution.

"As a leading recipient of geofence and keyword warrants, Google is uniquely situated to provide public oversight of these abusive practices," the groups wrote in the letter.

Google, in an amicus brief filed in a case in Virginia federal court and cited by the groups, said that from 2017 to 2019, the company saw a 75-fold increase in geofence warrant requests.

Keyword warrants are another method to identify users who searched for a specific keyword, phrase or address, the groups said.

"These blanket warrants circumvent constitutional checks on police surveillance, creating a virtual dragnet of our religious practices, political affiliations, sexual orientation, and more," they wrote, referring to both keyword and geofence warrants.

The groups want Google to expand its regular transparency report to give monthly information on the non-traditional court orders the company gets, writing that tracking the growth of these tactics will provide the organizations "vital ammunition in the fight for privacy."

"Currently, Google lumps these invasive court orders in with standard warrants, but geofence and keyword warrants pose a much more potent threat," Albert Fox Cahn, executive director of the Surveillance Technology Oversight Project Executive, said in a statement.

"A single one of these orders can track every person at a protest, a house of worship, or a medical facility. With more transparency, we can amplify efforts to outlaw these sweeping search warrants."