Cozen O'Connor is keeping up its raid on Buchanan Ingersoll & Rooney, with the departures cutting deeply into Buchanan Ingersoll's labor and employment group.

As expected, the firm formally announced Monday that it brought on another 17 Buchanan Ingersoll attorneys, in addition to the three Pittsburgh partners who joined the first week of May. Sources said even more lawyers are likely to leave Buchanan Ingersoll for Cozen O'Connor in the near future, and that the total moving could be as high as 30.

Cozen O'Connor and Buchanan Ingersoll had briefly discussed the possibility of a merger within the past year, multiple sources said, but did not get far in their talks. Both firms declined to comment on whether merger discussions took place.