US warplanes have carried out new air strikes on Islamic State (IS) militants in Iraq and Syria, hitting vehicles and arms dumps, the US military says.
Eight IS vehicles were damaged near Abu Kamal on the Syria-Iraq border, and two others in Deir al-Zour in the east of Syria, the US Central Command said.
In Iraq there were strikes on IS targets west of Baghdad and southeast of Irbil, near Kurdish territory.
Earlier there were air strikes on IS near the border with Turkey.
US President Barack Obama has condemned IS "fanaticism", in a speech to the UN General Assembly in New York.
"There can be no reasoning - no negotiation - with this brand of evil. The only language understood by killers like this is the language of force," he said.
He urged Muslims to reject the ideology of IS and al-Qaeda.
He said the US "will work with a broad coalition to dismantle this network of death.
"In this effort, we do not act alone. Nor do we intend to send US troops to occupy foreign lands. Instead, we will support Iraqis and Syrians fighting to reclaim their communities. We will use our military might in a campaign of air strikes to roll back Isil [IS].
"We will train and equip forces fighting against these terrorists on the ground. We will work to cut off their financing, and to stop the flow of fighters into and out of the region. Already, over 40 nations have offered to join this coalition. Today, I ask the world to join in this effort," he said.
The well-armed Sunni Muslim IS militants have seized large areas of Syria and Iraq, vowing to establish a hardline caliphate ruled by Sharia. They have beheaded Western hostages and have persecuted Christians, Yazidis and Shia Muslims, whom they treat as heretics.
Turkey border crisis
Syrian activists reported strikes around the Kurdish town of Kobane near Turkey, which has been besieged by IS fighters for several days.
Witnesses saw two military aircraft approaching from Turkey but Turkish officials denied its airspace or bases had been used in the attack.
The US-led coalition expanded its raids against IS into Syria on Monday. The US said Saudi Arabia, the United Arab Emirates, Jordan, Bahrain and Qatar had all "participated in or supported" the strikes.
But the aerial bombardment near Kobane, which happened at about 01:00 local time (22:00 GMT), has not been confirmed by the US or any coalition member.
Turkish military sources said neither its air force nor the US airbase at Incirlik in southern Turkey had been used.
The US has launched nearly 200 air strikes against IS in Iraq since August.
The IS advance has created a refugee crisis in neighbouring Turkey. Aid agencies said some 130,000 Kurdish refugees, most of them from Kobane, crossed into Turkey at the weekend.
The US air strikes on Tuesday also targeted Khorasan, a shadowy group of Al-Qaeda fighters in Syria's Aleppo province. The US military believes that attack killed Khorasan's leader Fadhli, a US official quoted by Reuters news agency said.
Meanwhile, the BBC understands that the UK Parliament will be recalled on Friday to discuss Britain's possible role in air strikes on IS targets.
Speaking on Tuesday, UK Prime Minister David Cameron said an international coalition was needed to "destroy" IS, adding that it was a fight "you cannot opt out of".
The Dutch government is also considering military action and will hold a special cabinet meeting on Wednesday to discuss deploying four F-16 fighter jets.
Turkey had initially refused to take part in military action against IS, but President Recep Tayyip Erdogan signalled a possible change in policy on Tuesday.
"We will give the necessary support to the operation. The support could be military or logistics," he told reporters in New York.
Correspondents say Turkey may be willing to get more involved after it secured the release of 49 Turkish hostages who had been held by IS militants in northern Iraq.
Anti-IS mood in Raqqa
The BBC's Mark Lowen, who is on the Syria-Turkey border, says Kurds still in Kobane reported a significant increase in shelling by IS militants on Wednesday morning.
A Kurdish military commander told Reuters news agency that IS boosted its forces after the air strikes, sending extra fighters and tanks to the outskirts of Kobane.
In the IS stronghold of Raqqa local people are looking forward to more air strikes on IS targets, according to Abdulkader Hariri, a man who got in touch with the BBC.
He says he is in the city, despite feeling "danger every day" because IS militants are against use of social media.
"Everybody is anticipating the second wave of attacks - especially at night. Surprisingly, many people are excited about hitting Isis [IS] more than anything - but those who live near Isis headquarters are afraid.
"There's only one hospital still operating now - the national hospital. Food supplies are available," he wrote.
Middle East press reacts to Syria strikes
The involvement of the region's countries "has given more legitimacy to the alliance" and embarrasses Russia and Iran, according to an editorial in Saudi newspaper Al-Watan.
In the conservative Iranian paper Khorasan, Ali Reza Rezakhah says the limited military operation shows that is it not "America's priority to fight [IS] nor [IS's] priority to fight America".
Salih al-Qallab defends Jordan's role in the air strikes in Jordanian daily Al-Ra'y, saying it is "no surprise" since terrorists inside Syria "went too far" in their attempts to carry out terrorist operations in Jordan.
Writing in Syrian daily Al-Thawrah, As'ad Abud says it is "new and unique" for Syrian territory to be attacked by an alliance involving Arab countries, especially when those countries once supported the terrorists it is attacking.
- Formed out of al-Qaeda in Iraq (AQI) in 2013, IS first captured Raqqa in eastern Syria
- It captured broad swathes of Iraq in June, including Mosul, and declared a "caliphate" in areas it controls in Syria and Iraq
- Pursuing an extreme form of Sunni Islam, IS has persecuted non-Muslims such as Yazidis and Christians, as well as Shia Muslims, whom it regards as heretics
- Known for its brutal tactics, including beheadings of soldiers, Western journalists and aid workers
- The CIA says the group could have as many as 31,000 fighters in Iraq and Syria
- The US has been launching air strikes on IS targets in north-eastern Iraq since mid-August
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