Russia and China, both allies of North Korea, expressed concern over an "escalation of tension in the region," the Russian Foreign Ministry said Saturday in a statement after a meeting in Moscow.

Separately, Chinese Foreign Ministry spokesman Qin Gang said in a statement that Beijing "hopes all parties will keep calm and restrained and jointly safeguard the overall peace and stability in this region."

North Korea has engaged in a series of acts this year widely seen as provocative. It fired a long-range rocket it said was a satellite in early April, and in late May it carried out its second underground nuclear test following the first in late 2006.

The country has also stoked tensions with rival South Korea and last month threatened "thousand-fold" military retaliation against the U.S. and its allies if provoked.

In addition, North Korea convicted two American journalists last month and sentenced them to 12 years hard labor for illegally entering the country. It is also holding a South Korean worker for allegedly denouncing its political system.

The secretive communist country is believed to be undergoing a political transition in which 67-year-old leader Kim Jong Il appears to be laying the groundwork to transfer power to one of his sons. Kim himself took over from his late father, the country's founder.

South Korean officials said Saturday's launches came throughout the day and were part of military exercises. The North, which had warned ships to stay away from waters off the east coast through July 10, also fired what are believed to have been four short-range cruise missiles Thursday.

Speculation had been building for weeks that the launches were coming. The key question has been whether the North might fire an intercontinental ballistic missile, as it vowed to do in late April.

Despite a Japanese newspaper report last month that one might be launched toward Hawaii in early July, U.S. officials have noted no such preparations, which are complex, usually take days and are often observable by spy satellites. Still, that hasn't stopped Washington from boosting missile defenses as a precaution.

Yonhap also reported that the North is believed to have spent between $34 million and $46 million in test-firing the seven missiles Saturday. It cited no source.

South Korea's Defense Ministry said it cannot confirm the report.

South Korea's Yonhap news agency suggested launch activity may be winding down, at least for now. It reported late Saturday, citing an unidentified military official, that the North was pulling personnel from its missile launch site and allowing ships to sail again off the coast. The Defense Ministry said it could not confirm the report.