The military said the UAV had crashed and China's border troops have conducted identification and verification of the drone.
It said only that the drone crashed in "recent days" and did not give a location. Chinese military's western theatre command jurisdiction covers nearly all of the 3488-km Line of Actual Control (LAC), including Tibet's border region with India and the Ladakh region.
"We strongly express our dissatisfaction and opposition". "We will fulfil our mission and responsibility and defend China's national sovereignty and security resolutely", he added. saying, without giving details about when or where the incident happened.
However, there was no immediate response from the Indian Defence Ministry.
The External Affairs Ministry said in a statement on Tuesday that Wang, along with Russian Foreign Minister Sergey Lavrov would attend the meeting on December 11 to be hosted by External Affairs Minister Sushma Swaraj.
China's Foreign Ministery spokesperson Geng Shuang told media that Wang will hold talks with top Indian officials on sidelines of Russia, India and China (RIC) Foreign Ministers meeting.
China claims Arunachal Pradesh as part of South Tibet.
The 73-day stand-off ended in August with troops of both nations pulling back their troops from the disputed territory claimed by both Bhutan and China. India objected to the construction highlighting its security concerns.
The standoff began in mid-June after Chinese troops started building a road on the remote Doklam plateau.
Wang's visit is regarded significant as it is first by a top Chinese official to India after the Doklam standoff which strained ties between the two neighbours.