In 2014-2016, the United States launched four satellites under the GSSAP program aimed at controlling the space in the interests of the US Air Force.
The Astro Space Center's document said that the Russian systems had registered intensive movement of all four GSSAP satellites.
For example, one of the GSSAP satellites, which was launched in 2014, had carried out more than 400 manoeuvres before 2018, according to the document.
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The paper added that sometimes the GSSAP space vehicles were approaching other US satellites to inspect them.