UPDATE 3-Leap Wireless increases size of share offering

* Raises offering to 7 mln shares from 6.1 mln

* To use proceeds for network expansion, acquisitions

* Shares fall as much as 9 percent (Adds estimates of net proceeds and senior notes; analyst comment; updates shares)

By S. John Tilak

BANGALORE, May 28 (Reuters) - Leap Wireless International Inc (LEAP.O) increased the size of its public offering to 7 million common shares from 6.1 million and said it may use the proceeds for its expansion plans or acquisitions.

The company estimates net proceeds of about $264 million from the offering.

Shares of the low-cost mobile carrier, which also announced the pricing of its $1.1 billion senior secured note offering, closed down 8 percent Thursday.

Leap has been rapidly expanding into new markets, and it recently entered Chicago and Philadelphia.

"It's a net positive that Leap was able to raise capital in this market environment," said Soleil/Nelson Alpha Research analyst Michael Nelson.