San Francisco, Nov 22 (IANS): Android smartphones have reportedly been gathering users' location data and sending it to Google even when the location services were turned off and there was no SIM card in the device.

"Even if you take all of those precautions, phones running Android software gather data about your location and send it back to Google when they're connected to the internet," Quartz reported late on Tuesday.

The tech giant has reportedly confirmed the practice of gathering location data.

"In January this year, we began looking into using Cell ID codes as an additional signal to further improve the speed and performance of message delivery," a Google spokesperson was quoted as saying.

Android phones have been collecting the addresses of nearby mobile towers -- even when location services are disabled -- and sending that data back to Google.

This makes search engine giant and the unit of Alphabet behind Android to have access to huge amount of data that invades their privacy.

Users cannot opt out of this even when their devices are factory reset.

In October, several Google Home Mini devices reportedly malfunctioned and recorded audio in the background in the owners' homes, instead of only waking up when a specific trigger word was used.

Meanwhile, Google's privacy policy does include the following section on "location information" (below) which states that users of "Google services" may have their location data collected, including mobile tower data.