Initial tests have found that between 10 and 20% of anchors in these locations would fail at a force of less than 5 kN. (Anchor forces during falls tend to be anything between 2 and 7 kN, depending on the fall severity)
More work is being done, but of particular concern is noted that not all weakened anchors showed visible signs of cracking.
Read the full report and UIAA warning here
Climbers are advised to check anchors carefully, and to find out the history of anchors with local climbers before using them.