SpaceX CEO Elon Musk said that he had activated satellite Internet service Starlink in Ukraine.

The move came after Ukraine’s First Vice Prime Minister and Minister of Digital Transformation Mykhailo Fedorov called for help from the billionaire on Saturday, as the country faces disrupted Internet connectivity.

"While you try to colonize Mars — Russia try to occupy Ukraine! While your rockets successfully land from space — Russian rockets attack Ukrainian civil people! We ask you to provide Ukraine with Starlink stations and to address sane Russians to stand," Fedorov said on Twitter.

Musk responded: "Starlink service is now active in Ukraine. More terminals en route."

The usefulness of the service may be limited until modems are made available. Starlink only works with proprietary $499 dishes. It is not clear how many, if any, modems are currently in Ukraine.

Update: On February 28, Fedorov tweeted an image of the back of a truck filled with Starlink dishes. "Starlink — here. Thanks, Elon Musk," he said.

"You are most welcome," Musk replied.

One customer tweeted that they were already using the platform:

But CitizenLab senior researcher John Scott-Railton has cautioned that the Russian military has a history of tracing satellite phone call signals in Chechnya to kill rebels.

Satellite Internet dishes have more directional signals, and are harder to spot, but Russia is believed to have destroyed such dishes in Syria.

"I've researched the role & risks of Internet & satellite communications during armed conflicts for a decade," Scott-Railton said. "I see a familiar mistake looming. Again."

Update: Satellite company Viasat has gone down in Eastern Europe, due to an apparent cyberattack.