TOKYO, June 13 (Reuters) - Japanese government bonds

(JGBs) rose on Friday as investors bought safe-haven assets

after Israel said it attacked Iranian nuclear targets, stoking

geopolitical worries.

The 10-year JGB yield fell to as low as

1.385%, its lowest since May 12. It was last at 1.41%, 4.5 basis

points (bps) lower than on Thursday.

Yields move inversely to prices.

"The yields fell sharply after the news about Israel's

attack," said Miki Den, a senior Japan rate strategist at SMBC

Nikko Securities.

Early on the day, Israel said it had struck Iranian nuclear

targets to prevent Tehran from developing atomic weapons, with

Iranian media and witnesses reporting explosions, including at

the country's main uranium enrichment facility.

The demand for safe-haven assets was a tailwind for

super-long JGBs, which have struggled to attract investors at a

series of auctions in the past few weeks.

The 20-year JGB yield fell 3.5 bps to 2.36%.

On Thursday, the outcome of the finance ministry's liquidity

enhancement auction for bonds with maturities between 15.5 and

39 years worsened from a similar auction in April.

But Japanese Government Bond #13, which has a maturity of 35

years, and #85, with a maturity of nearly 30 years, were among

the few tenors that got the highest bids, the finance ministry

said.

SMBC Nikko's Den said there was a demand from investors to

cover short positions of super-long bonds.

"They made short positions on those bonds, but then wanted

to buy them back after seeing news that signalled the finance

ministry's willingness to improve demand," said Den.

The yields on super-long bonds hit record highs in May but

were on the decline after Reuters reported last month that

Japan's finance ministry was considering reducing their sale.