Chinese news media say the country's first aircraft carrier has returned to the northeastern port of Dalian after completing its initial sea trials.

The Shanghai Daily reports that the carrier was towed back into the shipyard Sunday morning amid firecracker blasts and cheers. The report says that some navy personnel were seen walking on the deck, but that all the weapons were covered.

This refitted former Soviet vessel that China bought from Ukraine in 1999 began its inaugural sea trials last Wednesday, at a time of increased regional tensions in the South and East China Seas.

The United States has expressed concern about Beijing's lack of transparency regarding the carrier.

But Chinese officials have responded that the vessel is not a threat to anyone and that its primary purpose is scientific research and training. They also have pointed out that China is the only one of the five permanent members of the United Nations Security Council without an operational aircraft carrier.

The United States has sent two of its carriers to the region. The George Washington arrived Saturday in international waters off the coast of Vietnam and has invited Vietnamese military and government officials to visit the 333-meter Nimitz-class vessel. The Japan-based vessel is said to be on a goodwill tour of Asia-Pacific nations.

The USS Ronald Reagan aircraft carrier began a four-day visit to Hong Kong Friday. It offers visiting tours to the general public.

Taiwan responded to China's aircraft carrier trials by exhibiting a supersonic missile, which it called the “aircraft carrier killer.” The Hsuing Feng-3 was displayed against a huge photo of a burning aircraft carrier that bears a striking resemblance to China's carrier.

The French News Agency quoted legislator Lin Yu-fang as saying that Taiwan is developing a new mobile version of the missile, which will have a longer range and carry a heavier warhead.