Q: This task involves annotating the answer type to a given question that involve some kind of complex reasoning (including numerical reasoning). Note that the questions require looking at more than one part of the passage to answer. There are 3 possible answer types (i) spans, (ii) numbers and (iii) dates. If the answer can be found in the passage, label it as "span". If the answer is a number, label as "number". Similarly, label "date" if you think the answer to the given question is a date.
Passage: Because Bern and Zurich had been preparing the war for a long time, they seized the offensive. Bern opened the first war phase on 26 April, when its first troops crossed the river Aar at Stilli, to support Zurich with the occupation of Thurgau and the assault on the abbatial lands. In mid-May, about 3000 Zurichers, 2000 Bernese, 2000 Toggenburgers and 1800 Protestant Thurgauers marched into the Princely Lands and first hit upon the abbatial city of Wil, that fell on 22 May after a short siege. The allies then pushed forward to St. Gallen and occupied the Abbey of Saint Gall and the Vogtei Rheintal. The abbot fled to Neuravensburg, a lordship north of Lake Constance that the abbey had acquired in 1699. The five Catholic cantons did occupy Rapperswil, but initially left the abbot without any support. In concordance with contemporaneous laws of war, the abbey and its goods were put an under a military governance and the chattel and riches were abducted to Bern and Zurich.
Question: What were Bern and Zurich working on together?
A:
span