(Adds confirmation of the attack by General Dynamics in paragraph 2, additional comment in paragraphs 3-4 and 10)

MADRID, June 5 (Reuters) - Santa Barbara Systems, a General Dynamics subsidiary in Spain that is refurbishing Leopard tanks for delivery to Ukraine, suffered a cyberattack on its website, a pro-Russia hacker group said.

A spokesperson for General Dynamics confirmed that the defence contractor's Spanish unit had been targeted in an attempted cyberattack "that was detected immediately and has not compromised any of the company's systems".

They said the company decided to temporarily disconnect its website until an ongoing investigation concluded. "The company's sensitive data remains well-protected," the spokesperson added.

A spokesperson for General Dynamics in Germany said all of the company's operations in Europe were running normally.

The NoName hacking group claimed responsibility for the distributed denial-of-service (DDoS) attack via the Telegram messaging service.

These types of attacks direct high volumes of internet traffic towards targeted servers to knock them offline.

"We sent our DDoS-missiles against websites in russophobic Spain," the group, which often directs such actions against countries which support Ukraine, wrote on Telegram on Tuesday.

NATO said last month that Russia was behind an intensifying campaign of hybrid attacks on companies and infrastructure in member states, an accusation Russia dismissed as "misinformation".

Santa Barbara assembles heavy vehicles such as Leopard tanks and artillery equipment for the Spanish army and has been involved in refurbishing Spain's mothballed Leopard tanks for delivery to the Ukrainian army, according to the Defence Ministry.

Spain's National Cybersecurity Institute had warned the company in the past few days about the possibility of such attacks, the General Dynamics spokesperson in Madrid said.

Spain last week pledged 1 billion euros ($1.08 billion) in military support for Ukraine this year, which according to local media reports includes 19 Leopard 2A4 tanks. (Reporting by Inti Landauro and Andrei Khalip; editing by Aislinn Laing, Jason Neely and Jane Merriman)