Fumero, who plays Amy Santiago, posted a photo from the set, grinning at the camera alongside Terry Crews and Andre Braugher - who portray Captain Holt and Terry Jeffords, respectively.
Confirming filming had resumed after being interrupted due to the pandemic, Fumero wrote in the caption: "Ba ba ba back in the Nine Nine!!!! Yesterday, I was so excited to be back at work I forgot to take a pic to commemorate the occasion so here's from Day 2. #Brooklyn99."
Season eight - which will also be the show's last - started shooting back in December, but had to be put on hold because of the coronavirus pandemic.
However, after a few months of patiently waiting, Andy Samberg - who plays the programme's main protagonist Jake Peralta - finally revealed that things would be recommencing 'very soon'.
Telling LADbible about the hold-up, he said: "We started shooting, then we shut back down. So we're waiting to come back again.
"It's scheduled for the fairly near future for us to return. There are a few factors going on - the surge in the (Covid) numbers in Los Angeles is a big one.
"There is a continuity to the people and the stories and the set becomes its own organism and you don't want to disrupt that. I think you can (lose a bit of rhythm), and we'll find that out when we come back."
Samberg also said he was 'flattered' that the show has been so popular in the UK.
He continued: "We heard that it does really well in the UK, which is so exciting for me. And we've said multiple times, 'we've got to get over there'. And I'd love to.
"I try and catch UK comedy shows. I'm a big Toast of London fan. Matt Berry is the best. I love Ricky Gervais. Of course I'd do something with him.
"I did Cuckoo for BBC Three and Iove British comedy and the time I spent in London. It's really flattering that Brooklyn is so popular there."
While we're waiting for season eight to finish filming, fans in the UK can tide themselves over with the seventh series, which recently dropped on Netflix.