MANKATO, Minn. -- Brett Favre's spectacular stint with the Minnesota Vikings might be over.

Favre has informed the Vikings he will not return to Minnesota for a second season, according to multiple reports.

Favre has sent text messages to teammates saying, "This is it," league sources told ESPN NFL Insider Adam Schefter.

Vikings tight end Visanthe Shiancoe said Favre texted his teammates and told them he plans to retire. Shiancoe added he did not receive any direct messages from Favre, but learned of the texts from several teammates.

"He told a couple guys on our team he's going to retire," Shiancoe said after practice on Tuesday. "He hasn't told me yet. I'm going to check my phone right now, but it hasn't been said publicly yet so I don't know what to believe."

However, the Vikings reportedly are ready to increase Favre's salary for this season in order to get him to hold off on retirement for another year.

Sources told the Star Tribune that the Vikings have offered to increase Favre's salary to $16 million guaranteed -- $3 million more than he was scheduled to make this season, plus another $4 million in incentives that could potentially pay Favre $20 million total for the 2010 season.

Neither Favre nor the Vikings has confirmed the news.

Vikings coach Brad Childress said Tuesday that he has talked to Favre in the past 24 hours, but was unaware of the reports of Favre's apparent decision to retire.

"I'm not a big hearsay person," Childress said. "I've got to hear it from the horse's mouth."

Childress told the NFL Network that the Vikings would be prepared if Favre didn't return.

"The same plays are being installed whether [Favre] was here or the guys that are here are here," Childress said.

After the Vikings completed a morning practice, Childress would not confirm Favre's status with the team and called it a "fluid situation." He told reporters that he had not heard from Favre directly about the decision, but said he could have a message waiting for him from the quarterback.