* Murcia demoted for not meeting financial criteria
* Mirandes to replace them in the second division (Adds LFP president quotes)
MADRID, Aug 7 (Reuters) - Spain's professional league (LFP) has demoted Real Murcia from the second division to the third tier and fined them 180,000 euros ($240,800) after they failed to get their finances in order.
A delegation from the debt-ridden club, led by coach Jose Manuel Aira and accompanied to the LFP headquarters in Madrid by several hundred noisily protesting fans, failed to prevent the league from ratifying the sanctions on Thursday.
Murcia finished fourth in the second division last term but failed to make it through the promotion playoffs. Their place next season will be taken by Miranda de Ebro-based Mirandes, who finished 19th and were relegated, the LFP said in a statement.
LFP president Javier Tebas noted at a news conference that 40 of the 42 professional clubs in Spain's first and second divisions had backed the league's financial rules and Murcia had been punished because they owed 13 million euros in tax arrears.
Many Spanish clubs have been afflicted with serious economic problems in recent years due to overspending and owe hundreds of millions of euros in unpaid taxes.
"The important thing is to protect the integrity of the competition and try to make clubs as equal as possible in financial terms," Tebas said.
"The clubs want everyone to pay their players, pay their taxes, social security, their suppliers and their debts," he added.
"That's the pressure we are under and we prefer 100 demonstrations like the one we had today before accepting clubs with these financial problems."
Murcia, based in the eponymous city in south-east Spain, have been demoted from the second division once before, in 1992 when they failed to comply with new rules on the structure of soccer clubs set out in government legislation.
They are the first Spanish side to be demoted twice, local media reported.
($1 = 0.7474 Euros) (Reporting by Iain Rogers, editing by Justin Palmer)