WASHINGTON - U.S. consumer prices increased 0.6% in June, after three months of declines, with a big jump in gasoline prices accounting for over half of the gain.The Labor Department reported Tuesday that the increase in its consumer price index followed declines of 0.4% in March, 0.8% in April and 0.1% in May as the hit to demand caused by the widespread shutdowns of the economy kept a lid on prices.The June report showed that energy prices jumped 5.1% with gasoline costs surging 12.3%.