* Investors buy superlongs after yields hit multimonth highs

* BOJ's outright JGB buying operation outcome also welcomed

* 2-yr/10-yr pulls away from 3-½ year high

* 5-yr Japan sovereign CDS indication tightens

By Shinichi Saoshiro

TOKYO, Nov 11 (Reuters) - Japanese government bonds surged on Wednesday, with the benchmark 10-year yield pulling away from five-month lows, as investors hunted for bargains a day after a government show of concern over rising long-term rates.

Tuesday's well-received U.S. 10-year note auction helped kick-start an early JGB rise.

Market players said JGBs extended gains as domestic investors including life insurers and pension funds emerged to buy super-long JGBs after 20- and 30-year yields spiked this week to multi-month highs.

The outcome of the Bank of Japan's regular operation to buy a total of 350 billion yen ($3.9 billion) of JGBs outright from the market also buoyed bonds. The BOJ was not flooded with offers to sell JGBs, suggesting bond dealers were not in a rush to dump their inventories. [ID:nBOJJA002B] [ID:nBOJJA002A]