Research firm ComScore says Google increased its share of the US internet search engine market in October, taking share away from rivals Yahoo and Microsoft.

Google widened its lead over the competition by winning 58.5 percent of all US searches last month, up 1.5 percentage points over September. Yahoo took second place with 22.9 percent of the search market, down from 23.7 percent, while third ranked Microsoft dropped to 9.7 percent from 10.3 percent.

Ask Network remained steady at fourth place with 4.7 percent of the US search market in October, while Time Warner Network dropped slightly to 4.2 percent from 4.3 percent a month earlier, ComScore reported.

Google captured 6.1 billion of the 10.5 billion internet searches Americans conducted in October, ComScore said, far more than second place Yahoo's 2.4 billion.