Marseille's scheduled Ligue 1 clash at home to Rennes was postponed three hours before kick-off after "a few hundred individuals from Ultra supporter groups" stormed the club's training ground.
L'OM condemned the "unacceptable attack" at the Robert Louis-Dreyfus centre, which required police intervention, in a statement on their official website.
"Thefts were committed and vehicles were damaged. Five trees were burned with the sole desire to destroy," the club said. "The damage inside the buildings amounts to several hundreds of thousands of euros."
Andre Villas-Boas' team have suffered four straight losses in all competitions, sparking ire among hardcore fans.
The statement continued: "These irresponsible and unacceptable actions must be condemned with the utmost severity. Olympique de Marseille has all the evidence – it was immediately forwarded to investigators. Complaints will be filed in the coming hours to assert the rights of the club against this barbarism."
Earlier, Lens climbed to sixth with a 2-1 victory at Montpellier as Cheick Doucoure and Gael Kakuta fired the promoted club beyond their out-of-form hosts, for whom teenage substitute Elye Wahi struck an acrobatic effort.
In Spain, Real Madrid suffered a huge dent to their LaLiga title ambitions following a surprise 2-1 home defeat by Levante at the Alfredo Di Stefano Stadium.
The reigning champions were reduced to 10 men after just nine minutes when defender Eder Militao was shown a straight red card.
Marco Asensio put Real 1-0 up just moments later, but Jose Luis Morales levelled for Levante before the interval, with Roger netting the winner 12 minutes from time.
The result leaves Zinedine Zidane's men seven points behind leaders Atletico Madrid, having also played two more games.
Sevilla climbed to third place, a point behind Real, as Lucas Ocampos' penalty and star man Joan Jordan's second-half strike earned them a 2-0 win at Eibar. The latter has recently been linked with a move to Arsenal.
Valencia pulled away from the relegation battle and into mid-table with a 1-0 home against Elche, secured by Daniel Wass' 22nd-minute headed goal.
Elsewhere in LaLiga, Alexander Isak scored right at the death to cancel out Dani Parejo's goal as Real Sociedad forced a 1-1 draw at Villarreal.
Bayern Munich avenged their only competitive defeat of 2020 by overpowering Hoffenheim 4-1 at the Allianz Arena.
Jerome Boateng and Thomas Muller gave the leaders a two-goal cushion before Andrej Kramaric scored to make things interesting heading into the break, delaying Manuel Neuer's wait for a 200th Bundesliga clean sheet.
However, Robert Lewandowski and Serge Gnabry wrapped up the win in the second half.
Christopher Nkunku scored the only goal as RB Leipzig beat Bayer Leverkusen 1-0 to remain Bayern's closest challengers, albeit with a gap of seven points still to overcome.
Andre Hahn gave Augsburg a shock 10th-minute lead at Borussia Dortmund before Thomas Delaney and Jadon Sancho turned the game on its head with goals either side of half-time. Felix Uduokhai's own goal ensured a 3-1 home for Dortmund, who are stuck in fifth thanks to Eintracht Frankfurt's win.
The Eagles occupy the last Champions League place after beating Hertha Berlin 3-1.
After a goalless first half, Andre Silva's brace and a Martin Hinteregger strike sealed the win for Eintracht, although another former AC Milan frontman, Krzysztof Piatek, notched for Hertha with 66 minutes gone.
Alassane Plea cancelled out Robin Knoche's goal for Union Berlin as Borussia Monchengladbach forced a 1-1 draw in the capital, while Werder Bremen shared the same scoreline with Schalke thanks to goals from Kevin Mohwald and Omar Mascarell.
Zlatan Ibrahimovic missed a penalty but his blushes were spared as Ante Rebic tucked away the rebound to help AC Milan win 2-1 at Bologna and maintain their Serie A lead.
Franck Kessie doubled the Rossoneri advantage in the second half, with Andrea Poli pulling a goal back late on.
Inter Milan are only two points behind their city rivals after thrashing Benevento 4-0 at San Siro. Riccardo Improta helped the Nerazzurri out with an early own goal, with Lautaro Martinez's strike and Romelu Lukaku's brace killing off the contest.
Champions Juventus remain in touch with the top two after Federico Chiesa and Aaron Ramsey led the Bianconeri to a 2-0 triumph at Sampdoria.