PORTLAND, Ore. (KOIN) — Multnomah County officials suspect that Portland’s streak of high temperatures has caused two more heat-related fatalities, which brings the death toll up to six.

The Medical Examiner’s Program began investigating the fifth death late on Friday, Aug. 18.

According to the county, the individual was found dead in Northeast Portland and was last known to be alive on Sunday, Aug. 13 — which marked the beginning of triple-digit heat in the area.

Officials said the individual “may have been exposed to any of the elevated temperatures experienced this week.”

Also on Friday, Aug. 18, the sixth potential heat-related death was reported to the Medical Examiner’s Office. The office announced that the individual died in North Portland.

The county previously reported that it was investigating four other potential heat-related deaths.

The first victim was found in Southeast Portland on Monday when the peak reached 106 degrees, and the second victim died on Tuesday when it was about 102 degrees outside.

On Wednesday, another individual was found deceased in Northeast Portland when temperatures measured at 102 degrees. The fourth individual died in the same part of the city on Thursday, when temperatures were around 92 degrees.

The county hasn’t released any of the individuals’ names. According to officials, heat-related death investigations can take weeks or months.