BOJ bought 500 bn yen of 5 to 10 yr JGBs (vs. 450bn prior operation)

And a minor flurry of USD/JPY buying on that - also buying unlimited quantities of 10yr JGBs at 0.11% yield

We flagged the BOJ to buy JGBs earlier: USD/JPY on the move, ticking a wee bit higher

The BOJ offering to buy 'unlimited' quantities of 10yrs is what prompted the more persistent USD/JPY buying. The yield on the 10 yr had risen above 0.1% earlier - the BOJ has a target for this yield around 0%, which means they'll buy it to push the yield lower. This part of their Yield Curve Control policy.