Unfortunately another escape occurred at Planckendael last month.
On July 18th two addaxes escaped, but the story only became public now. They succeeded in pushing open the door of their stable, then jumped the fence.
One ended up in the zebra paddock, one in the savanna paddock. The animals were never outside of an enclosed area and keepers succeeded in leading them back to their enclosure, so they didn't have to be caught or sedated. The animals were also uninjured.
Although the animals were never in a public area, the zoo opened an hour and a half late that day. Visitors were wrongly told there was a technical defect, which the zoo admits was a communication error.
Sadly I could only find the full story in a subscription only article from Gazet van Antwerpen or Het Nieuwsblad.
Twee antilopen ontsnapt in Planckendael
Antilopen ontsnappen uit verblijf: vierde ontsnapping in twee jaar voor Planckendael
The GvA article also mentions that this was the fourth escape at Planckendael in two years, after lioness Rani (shot dead), a crested macaque (sedated and captured the same day) and the birds from the South American aviary (quite a few of those have been recaptured, but some are still out or missing). Planckendael's spokeswoman in the article pointed out that the circumstances were always different and that extra measures to avoid escapes of dangerous animals have been taken.
Of course it is unfortunate that this escape occurred, and I also find it regrettable that they chose to not communicatie accurately on the day itself, and did not make this public until now. I don't think they took the best route in terms of public perception and communication by doing so.
I personally don't think too much drama should be made about the escape, animals showing fear and flight responses is something that can happen, and you cannot always predict what an animal might do in such a situation. The animals never entered a public area, no animals were injured and no people were ever put in danger. I do however think they should thoroughly check the addax areas to ensure there aren't any things that should be fortified or modified. They got lucky this time, and something like this should preferably not happen again.
I also hope Planckendael will not get too much trouble from the animal welfare authorities or from zoo detractors for this one.