Pull quotes from the below text :- Russian President NAME_1 will "feel a tremendous need to reassert authority" after a rebellion staged by the NAME_2 Group reached halfway to Moscow before it was called off, a former U.S. Marine Corps intelligence officer said on Saturday.

Speaking on NewsNation, NAME_3, now CEO of Global Risk Intelligence and Planning, warned that the Russian leader "could be very dangerous" as he seeks to regain his grip on power.

In a matter of hours, NAME_2 Group units were able to capture military sites in Rostov-on-Don in Russia on Saturday before advancing north towards the Russian capital, prompting the nation's military to hastily prepare defensive measures. NAME_2 Group's leader NAME_4 declared war against the Russian Ministry of Defense on Friday after the Russian military allegedly carried out an attack against and killed some of his troops who were stationed in Ukraine.