IndonesiaÕs National Transportation Safety Committee (KNKT) sub-committee head for air accidents, Nurcahyo Utomo speaks during a news conference on its investigation into a Lion Air plane crash last month, in Jakarta, Indonesia, November 28, 2018. REUTERS/Willy Kurniawan

JAKARTA (Reuters) - An Indonesian investigator said on Wednesday it was too early to say whether issues with an updated Boeing 737 anti-stall system contributed to the crash of a Lion Air flight last month that killed all 189 people on board.

Nurcahyo Utomo, an investigator at Indonesia’s transport safety committee (KNKT), said the agency had not yet determined if the anti-stall system, which was not explained to pilots in manuals, was a contributing factor.

“We still don’t know yet, if it contributed or not,” he said in response to a question at a briefing. “It is too early to conclude for now.”

Contact with the jet was lost 13 minutes after it took off from Jakarta, heading north to the tin-mining town of Pangkal Pinang.