TOKYO, April 14 (Reuters) - Japanese government bonds firmed on Friday, with the superlong tenor gaining the most after solid demand in the previous session's sale and as the Bank of Japan kept amounts intact in its bond buying operations from its previous purchase offer.

Skidding regional equities markets and ongoing tensions in North Korea also added to the appeal of safe-haven sovereign debt, while liquidity in global markets has thinned this week due to Passover and Good Friday observances.

The market for U.S. Treasuries finished trading early on Thursday, and will be closed Friday. The benchmark 10-year Treasury yield touched its lowest since November overnight.

Global bond yields have fallen on rising geopolitical concerns after the U.S. Navy fired 59 Tomahawk missiles at a Syrian airfield last week in response to a deadly gas attack. That raised concerns about U.S. President Donald Trump's plans for North Korea, which has conducted missile and nuclear tests in defiance of U.N. and unilateral sanctions.

On Friday, the BOJ offered to buy 280 billion yen ($2.57 billion) of one- to three-year JGBs, 350 billion yen of three- to five-year JGBs, 200 billion yen of 10-25 year JGBs and 100 billion of JGBs maturing in more than 25 years.

The 30-year JGB yield fell 3 basis points to 0.760 percent , its lowest since mid-January, helped by solid demand at the previous session's 30-year JGB sale.

The benchmark 10-year JGB yield fell half a basis point to 0.015 percent, while 10-year JGB futures ended up 0.18 point at 151.09.

($1 = 108.8800 yen) (Reporting by Tokyo markets team; Editing by Subhranshu Sahu)