The incident occurred on August 13 with troops of People's Liberation Army (PLA) coming insiide Arunachal after they were stopped by the Indian troops, Defence sources said here today.
Both sides showed banners to each other to leave the area, the sources said in Delhi.
However, Chinese soldiers reportedly stayed put and left after two days, they said.
Official sources in Itanagar said the Chinese troops went back after a 15-minute Border Personnel Meeting.
The Chaglagam area, also known as "fish tail" because of the shape of the LAC in the area, has consistently seen intrusions by the Chinese in the past but they have always gone back immediately.
China lays claim over entire Arunachal Pradesh which is rejected by India.
Both the Army headquarters in Delhi and the External Affairs Ministry downplayed the incident.
"We don't take up non-events in diplomatic practice. What has happened or not is upto sentinels of our borders to answer. They know the factual position on this and I think they have answered that.
He was asked whether India has taken up with China the issue of incursion in Arunachal Pradesh.
