Construction of facilities to enhance the missile launch pad in North Korea’s northwestern town of Dongchang-ri, appears to have been completed, a U.S. research website said, reinforcing the speculation that Pyongyang may engage in a provocative act in the coming months.

Based on its analysis of commercial satellite imagery, 38 North, run by the U.S.-Korea Institute at Johns Hopkins School of Advanced International Studies, claimed that a new phase of construction, which began in spring 2015 after the completion of a taller gantry tower, appears to have been completed.

“A movable support platform is probably now finished and apparently is a much larger structure than originally anticipated, measuring about 24 meters long, 30 meters wide and about 33 meters in height,” the website said, adding that a launch-support building at the end of the pad has also been completed.

Each stage of space launch vehicles and payload can be prepared horizontally in the new launch-support building and then transferred to the movable support structure, where they will be erected vertically, checked out and finally moved to the launch tower, the website explained.

Speculation has been rising that Pyongyang could set off military provocations around Oct. 10, the 70th anniversary of the foundation of the North’s ruling Workers’ Party, in order to strengthen national unity and show off its military strength to the outside world.

The U.S. website, however, pointed out that there are still no indications that any test preparations are underway to support a long-range rocket launch. It also noted that there was no public evidence to suggest that a decision had been made by the North Korean leadership to push ahead with a missile launch.

“In the coming weeks, if preparations are indeed underway, we would expect to see other on-the ground indications at Sohae (the launch site) including increased rail activity and the possible arrival of missile-related railcars, activity at facilities associated with rocket assembly, the filling of oxidizer and fuel storage tanks associated with the launch pad, activity at range radars intended to track a launch and possibly the arrival of VIPs to observe a launch,” 38 North said.

Explaining the new facilities at the launch site, a Seoul official said that based on his analysis of the imagery, he has yet to discover any facilities which will be used to assemble each stage of a rocket for a launch.

“There were no facilities yet for the assembly of rocket components,” he said, declining to be named.

“Should the North launch a long-range rocket, it would separate each stage of the rocket, which has been developed at a factory near Pyongyang, then transport the parts via train or other vehicles to Dongchang-ri, and then put them together there for a launch.”

Regarding speculation of the North’s possible provocation, Pyongyang’s Deputy Ambassador to the U.N. Jang Il-hun told the press that his country is “free to do anything” as a sovereign state.

“We made it clear in the past that North Korea would respond to the U.S.’ military deterrence and pressure, with our modernized, expanded and strengthened nuclear weapons,” he said.

“Among all these possibilities, none of them has been ruled out, though I am not in a position to tell you about what exactly will happen.”

South Korea’s Unification Ministry said its military authorities and government are closely monitoring North Korea’s military activities, as there has always been the possibility of a North Korean provocation.

“We are prepared and ready to make our due, legitimate response should something (regarding the North) transpire,” ministry spokesperson Jeong Jun-hee said during a regular press briefing.

By Song Sang-ho(sshluck@heraldcorp.com)