Digimon Tamers Vol 2

From the Tokyopop edition

Two worlds collide as the rift between the Digital World and Earth grows unstable. While more and more Digimon start marking their territory on Earth, the technology investigation bureau enforces some big-brotherly rule (and we don't mean brotherly love). As more secrets about the real Digimon are revealed, three new players get pulled into the Tamer ring.

Source: Anime News Network Encyclopedia